DS was fine with wees as soon as he trained himself, but poos took about 7-8 months (he had just turned 4 when he "got" it). Sadly he doesn't recall his motivation (I did ask). But it was just time and making him clear up his underpants himself. Because poo goes... "in the loo!" DS was happy to be in a nappy until he saw his bestie using our loo (had seen him on the loo at nursery before) - he was flat-out refusing to use the loo/potty up til then, even when running around outside nude or sitting in front of the TV for up to 4 hours at a time (he was begging for a nappy at that point!).

DH tried the shaming method with both DS and me (as in, I'm a bad mother because our 4-year-old isn't perfect on the loo), which wasn't appreciated.