His birthday was the day before the cutoff - so if he'd been born one day later, he would've been in the later grade that we put him in anyway.
When it was time for school to start, he was such a clingy momma's boy. Seriously, he didn't go anywhere without clinging to my wife's leg. Waiting a year for him was absolutely the right choice - he wasn't ready socially or emotionally to be in school.
For other kids, I get that it might make sense for them to move ahead or stay in their "normal" year. But it didn't for him.