Castcastofusers.com

Example study

Restwell Daily Recovery Coaching

Restwell is a sleep and recovery coaching app for people who already own a fitness wearable (Apple Watch, Oura, Whoop, Garmin) but get no real guidance from the data. The app reads HRV, sleep stages, and training load from the wearable's API and turns it into one specific action for the day: go to bed by 10:40, skip the hard interval session today, 15g magnesium tonight. Not another dashboard, one instruction a day. $15/month, no hardware to buy.

A finished Cast study, read only. 16 interviews with AI users across 2 Ideal Customer Profiles (ICPs), run on October 18, 2026. Everyone quoted here is an AI user, synthesized to match an ICP. They are not real people.

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What the study found

Look first at how to prove the daily call and keep it nearly free of effort and cost, before testing any standalone fee.

Serious athletes like a single skip-or-push call but want proof against their own judgment before paying. Tired working parents already know they are run down and will drop anything that adds a task. In both groups, most resist a fee on top of the wearable.

Who was asked

2 Ideal Customer Profiles, each with its own cast.

A scene for the ICP Serious amateur endurance athletes

ICP A · 8 AI users

Serious amateur endurance athletes

Wearable-owning runners, cyclists and triathletes training 6+ hours weekly who race regularly and manage their own recovery.

Markets: United States

  • Trains 6+ hours per week
  • Races regularly
  • Owns and wears a wearable at least 5 days a week
A scene for the ICP Sleep-deprived working parents with wearables

ICP B · 8 AI users

Sleep-deprived working parents with wearables

Employed parents aged 35 to 45 with young children who own a wearable and see poor sleep data.

Markets: United States

  • Age 35 to 45
  • Has a child aged 0 to 8 living at home
  • Works 30+ hours a week

Top findings

What each group said, ranked by how many AI users said it.

ICP A · 8 interviews

Serious amateur endurance athletes

Athletes want one clear skip-or-push call, but they will not pay on top of their wearable until it proves itself against their own judgment.

  1. 1. The single daily instruction is the part that appeals8 of 8 AI usersNearly everyone said the gap is a clear call, not more data.
  2. 2. Athletes demand proof and a trial before any fee8 of 8 AI usersAlmost all asked for a free trial or a track record before paying.
  3. 3. A fee on top of the wearable meets resistance6 of 8 AI usersMany already pay for a wearable or training app and feel a free score should come with it.

ICP B · 8 interviews

Sleep-deprived working parents with wearables

Tired working parents ignore their wearable scores and would try a daily instruction only if it costs almost no time or money.

  1. 1. Parents know they are tired but cannot act on it7 of 8 AI usersThese parents already know they are run down and say the score adds nothing new.
  2. 2. Effort is the main adoption barrier, not curiosity8 of 8 AI usersNearly everyone said any setup, logging or daily check-in would make them drop the app.
  3. 3. A paid add-on faces strong price and free-score resistance7 of 8 AI usersMembers expect the wearable's score to be free and balk at a second subscription.

In their words

Verbatim, from the interviews.

“it gives one instruction a day instead of just a number, which is exactly what I've been missing”
Portrait of Kevin Morrow, an AI userKevin MorrowTallgrass Consulting, United StatesSkeptic · ICP A
“yeah, I know I'm wiped out, what am I supposed to do about it”
Portrait of Jessica Martinez, an AI userJessica MartinezHarbor Ridge Accounting, United StatesSkeptic · ICP B
“I'd want to see a clear track record first, ideally from someone with a similar schedule and race goals”
Portrait of Tyler Nguyen, an AI userTyler NguyenPinecrest Design, United StatesSkeptic · ICP A
“a single instruction I can read in a few seconds without opening anything else”
Portrait of Tyler Sørensen, an AI userTyler SørensenBrightline Dental, United StatesPragmatist · ICP B

How this study ran

One brief, one hour, no recruiting.

16
AI users cast
16
interviews held
8
questions asked
2
ICPs compared

The Casting Agent read the brief, proposed the ICPs and wrote one question list. Each AI user then answered every question in its own interview and the findings were written from those transcripts. AI users role-play a defined customer from what that customer would plausibly know and feel; they do not look anything up.

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