When to send it
Send it on WhatsApp the evening of the trial class, or the next morning at the latest. Someone weighing up a month of classes tends to decide quickly, often on the way home. A short message from the studio with the link, and their first name in it as ?name=, reads as a natural follow-up rather than a sales push.
Why these questions
The first page asks two things: a star rating for the trial class, and whether they're thinking of joining. The second is the important one. Most studios only learn that a trial didn't convert when the person never comes back, and this asks them directly, with "maybe, I'm still deciding" as an honest middle option.
People who are ready to sign up skip straight to the last question. Everyone else sees a checklist of what's holding them back: price, class times, location, the class level, or comparing other places. Each answer points to a different fix, from an intro offer to a new timeslot or a beginners' class. Anyone who says the studio isn't for them also gets an open question about what you could have done differently, which is where you'll hear the things nobody likes to tell an instructor in person.
The final question asks how they heard about you. Over a few months it shows which channels bring people who actually walk through the door, which is more useful than counting followers or clicks.
The coupon
A unique 10% code off the first month is the natural nudge for someone still deciding. It's personal to them, so it can't circulate in group chats and undercut your regular price. Everyone who finishes gets one, including people who say the studio isn't for them: people change their minds, and a code waiting in their messages makes coming back easier.
The survey has two end screens. People who said they're ready see a welcome note, and everyone else sees a plain thank-you. Both carry the coupon.
What to do with the answers
Reply personally to every "maybe" within a day or two. Their checklist answer tells you what to say: a quieter class time, a payment option, a beginners' session. Count the reasons each month; if one dominates, change that before you touch the price.
Once people join, switch to the studio class feedback form for regular classes. Software businesses facing the same question after a free trial can look at trial ended without upgrading.