There are many factors. The most important thing your child needs to succeed when going off to college is resilience. You need that when you get a bad grade for the first time or when you have a mean roommate or when your bf/gf breaks up with you. It also helps to have gone away before and had experience living away from your family. That is why sleep away camp is great preparation for college. It helps if you don’t have a mental illness, many of which have onsets around the time one goes to college. It’s helpful to have realistic expectations about what colllege is all about. You need to prepare for the the fact that it may not be “the best 4 yrs of your life”. It helps to not drink and smoke too much. That leads to all kinds of trouble that could lead to crashing and burning. Finally, it’s important to go to a school that is a good academic and social fit. Less problems if you choose wisely.