Benchmarks / SurveyBench / Should Corefit gyms stop opening 24 hours? / Gemini 4 Argon

Measured by Spring Prompt

Gemini 4 Argon: Should Corefit gyms stop opening 24 hours?

The decision: whether to close all 14 gyms between 11pm and 5am, close overnight only at the quietest gyms, or keep every gym open 24 hours. The brief and the data →

Verdict
✗ Not sound
Research score
88 of 100
Analysis rating
985
Head to head, this task
won 12 of 25

Why it is not sound

The analysis

  • Reported a material finding the data does not support
  • Missed a trap: Only current members were surveyed: people who joined for 24-hour access and have since left, and people who would join only because of it, are missing, so the survey cannot show what 24-hour opening does for recruitment or the brand; and night-shift workers are a small group whose answers carry little weight in the totals even though they depend on the hours.

Findings the judges found unsupported

  • To the Operations Director: While only 6% of members (2,316 people) actually enter between 11pm and 5am according to door records, closing all gyms overnight is too risky because of heavy usage by night-shift workers and severe knock-on effects on daytime members.The comments show concerns about crowding, not demonstrated severe knock-on effects on daytime members. Presenting those effects as established overstates the evidence.
  • To the Marketing Director: Closing overnight risks heavy member churn and widespread demands for fee reductions, because 24-hour access is a core brand promise even for members who never train at night.The projected losses of approximately 4,399 or 1,875 members turn hypothetical cancellation intentions into churn forecasts. No supplied evidence supports using the 'very likely' share as an estimate of actual cancellations, and the claimed industry norm is unsupported.
  • Closing between 11pm and 5am threatens retention among daytime and evening members by displacing overnight users into the 10pm-11pm and 5am-6am windows, which many members specifically choose to avoid crowds.The comments express anticipated crowding; they do not establish that displacement will occur or threaten retention. Broad arrival-time bands cannot establish dependence on the specific shoulder hours. There are 31 crowding comments, not 26, including four from reported overnight users rather than two.
  • Unstaffed overnight hours create safety anxieties for a notable group of daytime members, representing an operational and perceptual risk of keeping gyms open 24/7 without security improvements.The supplied comments contain 40 safety-related responses, not the reported 34. They support perceived safety concerns but do not establish an objective operational safety risk.

Scorecard

Numbers 11 of 11 right

QuestionIts answerTrue
What percentage of respondents reported at least one visit to a Corefit gym between 11pm and 5am in the last four weeks?✓14.9%14.9%
What percentage of all respondents said they would be likely (fairly or very) to cancel their membership if their home gym closed between 11pm and 5am?✓14.6%14.6%
Among respondents who reported at least one visit between 11pm and 5am in the last four weeks, what percentage said they would be likely (fairly or very) to cancel?✓45.8%45.8%
Weighted so that respondents with at least one visit between 11pm and 5am in the last four weeks count as 6% of members (the door-entry figure) and the rest as 94%, what percentage would be likely (fairly or very) to cancel?✓11.4%11.4%
If the weighted share likely to cancel were applied to all 38,600 members, about how many members would that be?✓4,3994,383
Among respondents who reported at least one visit between 11pm and 5am in the last four weeks, in which band of the Q1 table does the median number of visits fall? Give the lowest value of that band (for example 4 for '4 to 7').✓22
What is the 95% margin of error, in percentage points, on the unweighted share of respondents who reported at least one visit between 11pm and 5am in the last four weeks?✓2.3 points2.27 points
Is the difference between North West England and North East England respondents in the share likely (fairly or very) to cancel statistically significant at the 95% level? (1 for yes, 0 for no)✓NoNo
How many of the open-text answers say that 11pm to 5am is the only time the respondent can train because they work shifts or nights?✓1516
How many of the open-text answers from respondents who visited between 11pm and 5am in the last four weeks say they would move to another gym?✓1819
What percentage of the members invited completed the survey?✓8%8%

Traps in the data 7 of 8 handled

  • ✓14.9% of respondents report at least one visit between 11pm and 5am in the last four weeks, against 6% of members in the door-entry records: members with a stake in the overnight hours were more likely to respond. Unweighted, 14.6% say they would be likely to cancel; weighted to the 6%, 11.4%.
  • ✓'Likely to cancel' answers (45.8% of overnight users, 14.6% overall) are stated intentions about a hypothetical closure, asked straight after members were invited to think about it.
  • ✓The mean number of overnight visits among overnight users (7.4) is pulled up by night-shift workers who come almost daily; the median is in the '2 to 3' band.
  • ✓The operations director believes almost nobody uses the gyms overnight. Partly true: 6% of members in the door-entry records (about 2,316 people). But night-shift workers (5.9% of respondents) mostly train between 11pm and 5am (77.8% of those who visited overnight usually arrive then) and are the most likely to say they would cancel.
  • ✓At Wakefield Calder Park (base 11), 54.5% of respondents used the gym overnight and 27.3% say they would be likely to cancel.
  • ✓North West England respondents (base 229) look more likely to cancel than North East England respondents (base 220): 19.2% against 13.6%, a gap that is not statistically significant at 95%.
  • ✓Only 950 of 11,900 invited members completed (about 8%); those who responded differ from those who did not, as the overnight-use skew shows.
  • ✗Only current members were surveyed: people who joined for 24-hour access and have since left, and people who would join only because of it, are missing, so the survey cannot show what 24-hour opening does for recruitment or the brand; and night-shift workers are a small group whose answers carry little weight in the totals even though they depend on the hours.

The analysis

Recommendation

Do not implement a blanket 11pm-5am closure across all 14 gyms. Keep the estate open 24 hours by default, and use full door-entry data (rather than survey samples) to evaluate whether a selective overnight closure trial is viable at the 2 to 3 genuinely quietest gyms where site-specific operating savings clearly exceed projected member churn.

What would change it

A site-by-site financial and door-entry audit showing that overnight operating costs (energy, security, maintenance, insurance) exceed the revenue of at-risk members—specifically if net savings per gym exceed the lost fees from ~4.9% to 11.4% of members cancelling—or a controlled trial at 1 to 2 low-usage gyms showing actual churn remains below 2% without triggering fee-reduction demands or 5am/10pm overcrowding.

Findings

  1. To the Operations Director: While only 6% of members (2,316 people) actually enter between 11pm and 5am according to door records, closing all gyms overnight is too risky because of heavy usage by night-shift workers and severe knock-on effects on daytime members.

    High confidenceBase 950

    Door-entry records show 6.0% of the 38,600 members visit between 11pm and 5am, whereas 14.9% of survey respondents (142 of 950, +/- 2.3 percentage points) claimed to do so, showing strong non-response bias from overnight users. Although the median overnight user only visits 2 to 3 times in 4 weeks, the mean is 7.4 visits because night-shift workers rely on these hours heavily: 80.4% of night-shift respondents (base 56) visit overnight, and 57.1% visited 15 or more times in the last 4 weeks.

  2. To the Marketing Director: Closing overnight risks heavy member churn and widespread demands for fee reductions, because 24-hour access is a core brand promise even for members who never train at night.

    Medium confidenceBase 950

    14.6% of all respondents (base 950) say they are likely to cancel if overnight hours are cut (45.8% among overnight users, base 142; 9.2% among non-overnight users, base 808). Weighting the survey to match the 6% door-entry reality reduces the overall likely-to-cancel rate to 11.4% (around 4,399 members), and even counting only 'very likely' cancellers (weighted 4.9%) projects to ~1,875 lost members. Furthermore, 24.0% of all members (and 17.8% of non-overnight users) joined specifically for 24-hour access (Q5), and 46 open-text respondents demanded a monthly fee reduction if hours are cut.

  3. To the Regional Manager: We should not base regional policy on the survey gap between the North West and North East, as the difference is not statistically significant and masks wide site-level variations within regions.

    High confidenceBase 449

    While 19.2% of North West respondents (base 229) say they are likely to cancel compared with 13.6% in the North East (base 220), this 5.6 percentage point gap is not statistically significant at the 95% confidence level (z = 1.60, p = 0.11), and self-reported overnight usage is actually slightly lower in the North West (14.0%) than the North East (15.0%). Site-level bases (ranging from 61 to 81, and just 11 at Wakefield Calder Park) are too small to reliably classify individual gyms as quiet or busy—for instance, Preston Centre in the North West has just 7.7% overnight usage (base 78) but 19.2% cancellation likelihood.

  4. Closing between 11pm and 5am threatens retention among daytime and evening members by displacing overnight users into the 10pm-11pm and 5am-6am windows, which many members specifically choose to avoid crowds.

    High confidenceBase 950

    22.0% of all respondents (base 950) usually arrive between 5am and 9am, and 35.4% between 5pm and 11pm (Q2). In the open-text responses (Q3), 26 respondents (24 of whom do not use the gym between 11pm and 5am) spontaneously expressed concern that closing overnight would push night users into their quiet 10pm or 5am workouts and create queues for equipment.

  5. Unstaffed overnight hours create safety anxieties for a notable group of daytime members, representing an operational and perceptual risk of keeping gyms open 24/7 without security improvements.

    Medium confidenceBase 239

    34 open-text respondents (all non-overnight users) spontaneously stated they would feel relieved or safer if the gyms closed between 11pm and 5am because unstaffed overnight opening makes them feel uneasy, vulnerable, or worried about accidents going unnoticed.

Caveats

  • Severe non-response bias toward overnight users: 14.9% of survey respondents report visiting between 11pm and 5am in the last 4 weeks, compared with 6.0% in September door-entry records (an over-representation of 2.5x). The overall response rate was 8.0% (950 of 11,900 invited).
  • Stated cancellation intent typically overstates actual churn: while 11.4% (weighted) say they are fairly or very likely to cancel, industry norms suggest actual cancellation is closer to the 'very likely' share (4.9% weighted, ~1,875 members) plus a fraction of 'fairly likely' respondents.
  • Small sample sizes per gym: individual gym bases range from 61 to 81 (and only 11 at Wakefield Calder Park, where 54.5% claimed overnight visits), making the survey unreliable for deciding which specific gyms are the 'quietest'.
  • Inconsistencies in self-reported open-text data: some respondents' home gym at Q6 does not match the location mentioned in their Q3 open text (e.g., M059 is registered to Leeds Kirkstall but mentions walking past Glasgow; M429 is registered to Leeds Kirkstall but mentions paying £17 at Preston), and two respondents classed as visiting between 11pm and 5am (M034, M735) state in Q3 that they never visit overnight.

Next steps

  • researchAnalyze 12-month door-entry logs across all 14 gyms by hour (specifically 10pm-11pm, 11pm-5am, and 5am-6am) and cross-reference with member tenure and fee levels.
  • decisionBuild a site-level profit-and-loss model comparing actual overnight operating costs against projected membership churn (modeling both the 4.9% 'very likely' and 11.4% weighted 'likely' cancellation rates).
  • experimentIf the P&L model identifies 1 to 2 gyms where savings clearly outweigh churn risk (e.g., low overnight door-entry sites like Preston Centre or Leeds Kirkstall, subject to door-log verification), run a 3-month trial of 11pm-5am closure at those sites only, offering affected overnight users multi-gym access or penalty-free cancellation.
  • monitorReview and communicate late-night safety protocols (e.g., visible panic buttons, CCTV monitoring, improved lighting) at gyms remaining open 24 hours.

Open-text themes it coded

No impact / never use the gym between 11pm and 5am 90Expect a lower monthly fee / discount for reduced hours 52Pleased or relieved / unstaffed overnight hours feel unsafe 42Displaced overnight users will crowd quiet 10pm-11pm or 5am-6am slots 31Would cancel membership or switch to a 24-hour competitor 20Night or shift work means 11pm-5am is the only time able to train 16

The survey it planned

1 screening question and 10 questions, as the model wrote them.

  1. S1

    Are you currently a paying member of a Corefit gym?

    One answer
    • Yes, I have an active membership
    • My membership is currently frozen or paused
    • No, I cancelled my membership
    • No, I have never been a Corefit member

    Continues if Yes, I have an active membership; My membership is currently frozen or paused

  2. Q1

    Which Corefit gym do you use most often?

    One answer
    • Aberdeen
    • Bradford
    • Carlisle
    • Dundee
    • Edinburgh
    • Glasgow
    • Hull
    • Leeds
    • Liverpool
    • Manchester
    • Middlesbrough
    • Newcastle
    • Preston
    • Sheffield
  3. Q2

    Thinking back to when you joined Corefit, which of the following were your main reasons for choosing Corefit over other gyms? Select up to three.

    Any that apply
    • Monthly price
    • No fixed-term contract (rolling monthly membership)
    • Convenient location
    • Open 24 hours a day
    • Range and quality of gym equipment
    • Classes and personal training options
    • Cleanliness and upkeep of the facility
    • Friend or family member was already a member
    • Other
  4. Q3

    In the past 3 months, at which of the following times of day have you entered a Corefit gym? Select all that apply.

    Any that apply
    • Early morning: 5:00am to 7:59am
    • Morning: 8:00am to 11:59am
    • Afternoon: 12:00pm to 4:59pm
    • Evening: 5:00pm to 8:59pm
    • Late evening: 9:00pm to 10:59pm
    • Overnight: 11:00pm to 4:59am
    • I have not visited a Corefit gym in the past 3 months
  5. Q4

    In the past 4 weeks, roughly how many times have you entered a Corefit gym between 11:00pm and 5:00am?

    One answer
    • None in the past 4 weeks
    • 1 or 2 times (less than once a week)
    • 3 or 4 times (about once a week)
    • 5 to 8 times (1 to 2 times a week)
    • 9 to 12 times (2 to 3 times a week)
    • 13 or more times (more than 3 times a week)

    Routing Shown only if Q3 is: Overnight: 11:00pm to 4:59am

  6. Q5

    What are your main reasons for using the gym between 11:00pm and 5:00am? Select all that apply.

    Any that apply
    • I work shifts, night shifts, or irregular hours
    • The gym is quieter and equipment is easier to get on
    • Childcare or caring responsibilities during the day and evening
    • It fits around my study schedule
    • I prefer working out late at night or very early in the morning
    • Other

    Routing Shown only if Q3 is: Overnight: 11:00pm to 4:59am

  7. Q6

    Corefit is reviewing its opening hours. If your gym changed its opening hours to 5:00am – 11:00pm every day (closed overnight between 11:00pm and 5:00am), with no change to your monthly membership fee, how would this affect your workouts?

    One answer
    • No impact – I never use or plan to use the gym between 11:00pm and 5:00am
    • Minor impact – I occasionally use or value those hours, but I could easily work out between 5:00am and 11:00pm instead
    • Moderate impact – I would have to change my routine and some workouts would be harder to fit in
    • Major impact – I could not fit in most of my workouts if the gym closed between 11:00pm and 5:00am
  8. Q7

    If your Corefit gym closed between 11:00pm and 5:00am every night (opening 5:00am to 11:00pm), what would you most likely do regarding your membership?

    One answer
    • Definitely keep my Corefit membership
    • Probably keep my Corefit membership
    • Not sure / would depend on what other gyms near me offer
    • Probably cancel my Corefit membership
    • Definitely cancel my Corefit membership
  9. Q8

    If you were to cancel your Corefit membership because of overnight closing, what would you do instead?

    One answer
    • Join another 24-hour gym within travel distance
    • Join another gym even if it is not open 24 hours
    • Work out at home or outdoors instead of using a gym
    • Stop working out regularly
    • Not sure

    Routing Shown only if Q7 is: Not sure / would depend on what other gyms near me offer; Probably cancel my Corefit membership; Definitely cancel my Corefit membership

  10. Q9

    Which of the following best describes your current work or study pattern?

    One answer
    • Regular daytime hours (for example, 9am to 5pm)
    • Shift work or irregular hours that include nights or late evenings
    • Shift work or irregular hours (daytime and evenings only)
    • Full-time student
    • Self-employed or freelance with flexible hours
    • Not currently in paid employment or full-time study
  11. Q10

    Which age group are you in?

    One answer
    • 16 to 24
    • 25 to 34
    • 35 to 44
    • 45 to 54
    • 55 to 64
    • 65 or over
    • Prefer not to say
Sample plan

Target population: All 38,600 current Corefit members across the 14 gyms in the north of England and Scotland. Sampling method: Stratified random sample drawn from the membership database using embedded database fields (home gym ID, region, tenure, and September 2026 door-entry overnight flag [entered 11pm–5am vs. did not]). Precision & Sample Size Note: Achieving +/- 8 percentage points at 95% confidence (worst-case p=0.50) within each of the 14 gyms independently requires n=150 completes per gym (2,100 total). Under the brief's constraint of ~1,000 total completes (equal quota of n=72–75 per gym, total n=1,008–1,050), worst-case gym-level margin of error is +/- 11.3 percentage points, though for lower-prevalence outcomes (such as overnight usage or cancellation rates around 6%–20%) n=75 per gym achieves +/- 5.4 to +/- 9.0 percentage points. We recommend either expanding total sample to 2,100 if strict +/- 8pp worst-case precision per gym is mandatory, or proceeding with n=1,050 (n=75 per gym) and using the full-population door-entry records to anchor gym-level overnight usage. Mitigation of Non-Response & Self-Selection Bias: Because only 6% of members used the gym overnight in September 2026, a general survey risks either having too few overnight users per gym to estimate their cancellation rate reliably, or suffering from self-selection bias if overnight users disproportionately respond. Therefore: (1) Use neutral email invitation wording ('Corefit Member Experience & Facilities Survey') that does not mention opening hours or overnight closures; (2) Within each gym, stratify invitations into two sub-strata based on database door-entry logs: Stratum A (entered 11pm–5am at least once in the past 3 months) and Stratum B (no 11pm–5am entries), oversampling Stratum A to secure at least 15–20 verified overnight users per gym (210–280 total across the chain) alongside ~55 non-overnight users per gym; (3) At the analysis stage, weight each gym's respondents back to that gym's exact database proportion of overnight vs. daytime-only members and overall member headcount.