Why did young Wes, who ran away from military school five times, finally decide to stay put?

Wes is finally persuaded to stay at military school by his mother, Joy, who tells him about the enormous financial sacrifices that had to be made to send him there. Once she'd made the decision to send him to military school, Wes's mother went around asking friends and family for a contribution towards the school fees. It was a substantial sum of money, one that Joy could never have afforded on her own. Wes's grandparents even used their retirement savings—with which they'd been hoping to fund their retirement in Jamaica—to send the young man to military school.
Wes didn't know about any of this before he was sent to Valley Forge. But now that he does, he realizes that he owes it to his family and friends to stay put and work as hard as he can to make a go of things.