A.B.
We just finished potty training last week, so this is fresh in my mind. I know all children are different but here is what worked for my son. He also wouldn't go poop on the toilet and I became frustrated. So out of desperation my husband took him to TRU and bought him 10 matchbox cars ($1 each). My son picked out the car he wanted to earn for the next poop. This seemed to be the motivation he needed. He did have a few accident, it wasn't magic, but it did give him the reinforcement he needed. After he earned all 10 cars I made him a chart with 10 spaces. This time we let him pick a big toy to earn after he got 10 stickers on his chart (one sticker for each poop). This time he chose a scooter and learned about delayed reward. He earned the scooter last week and we finished training. I would say constancy was really important for us. Hope this helps!