Oh, and the opposite situation, happened just last week....
Chap comes in, wife has bought him an hour TL as a birthday present. But he tells me he definitely wants to learn to fly, and probably buy his own helicopter afterwards. Short briefing, we go up, I let him have a go. He finds it really, really, really hard. Almost no matter what I do, he just can't manage it. He probably would in the end, but I can see he's getting discouraged. I take over, demonstrate a few things, and he asks me about helicopters. By the time we get back I'm fairly sure this chap will never try to fly a helicopter again. Tells me he enjoyed it, but it sounds false. Wife asks if he wants to book another lesson now; he says he'll phone us later. Haven't heard from him...and probably never will.
A TL lets people find out if they don't like flying when they thought they would, or find they love it and have to do it when they had no intention of doing so. Isn't that the whole point?