I was definitely potty trained too early, and have a theory that it led to my incontinence. Sounds weird, but what happened was I became actually too good at holding it, and my bladder neck tightened so much that by my teens I could barely pee. It got so bad that my kidneys were in extreme pain all the time. It would take me up to 15 minutes to void. Well, I had about 8 procedures done at 4 different hospitals until they figured out what was really wrong. I ended up getting both sphincters cut, and finally I could pee freely again. But of course this led to total incontinence. It could have been a different cause, but I believe I was hyper urine retentive at such an early age that it led to the failure of my control. I have also read that training too early can cause all kinds of problems for kids, such as constipation, which can cause urine accidents.