Here's a definition worth keeping: trust is relying on someone to do what's expected of them, before you know whether they will.
Read the last bit again. Before you know. That's the whole engine. If you waited for proof, you'd never trust anyone - because proof only arrives after you've already relied on them. Which means every relationship on earth runs on the same uncomfortable rule:
Trust is what you extend before the proof exists. Someone always has to go first.
Why your son won't go first
Somewhere along the way - a mate who shared the thing he said in confidence, an adult who promised & didn't show, a classroom that laughed - opening up got your son hurt. & broken trust doesn't stay a memory. It becomes a rule: don't expose yourself, you'll get let down. He doesn't remember every let-down. He just stops going first.
That's the wall you're living with. It isn't defiance & it isn't you - trust breaks anywhere, at school, in friendships, online. The wall is just evidence of how many times the rule got confirmed.
Slow to build, instant to break
Trust is a forward belief, which is why one broken expectation can level years of it - the moment someone doesn't do the expected thing, the belief is simply false. & it rebuilds the only way it can: expose a little, get met well, expose a bit more. Every round, the relying-before-knowing happens again at higher stakes. There are no shortcuts through that cycle. Only reps.
So the mentor goes first. Every time.
This is the quiet centre of what we do. A boy who's learned the rule can't be talked out of it - he has to watch it fail. So the mentor is the one who goes first: shows up the same day every week, does the expected thing, again & again, until the rule updates itself. Not a lecture about trust. A living counter-example.
& mum - the same is true for you. You've extended trust before - to the school, the GP, the program that fizzled - & been burned. If you're wary of us, that's not doubt. That's scar tissue, & it's rational. We don't ask you to feel certain. We ask for one call - & then we go first.