It is not your job to limit these possibilities."
How simple to state, how hard to do! I can't count how many times I've heard people say "I only want the best for my child." However, what you consider "the best" and what your child does may differ dramatically! This is especially true in adolescence. It's easy to name a ton of qualities you want your child to have, and equally easy to name a ton that you DON'T want your child to have.
However, if you want your child to enter a high-paying profession, and discourage a lower paying profession, you are limiting him. If you want your child to go to an ivy-league college and discourage going to a community college (or not going to college at all!), you are limiting her. If you want your child to get married and start a family, you are limiting him. If you want your child to be straight, observe a specific religion, control who they hang out with, etc... you are limiting her. I find it very sad when parents think less of their children for choosing to be a truck driver instead of a doctor, or choosing to live in a small town instead of travel.
One of the main reasons I wanted children in the first place is because a child is full of limitless possibilities. I like to ask myself "what if my son is artistic?" or "what if my son marries a black woman?" or "what if my son travels to Asia?" Some possibilities are hard to think about, such as "what if my child does hard drugs and gets addicted?" or "what if my son spends time in prison?" I will do my best to see that my son makes choices based on not only himself and what feels good in the now, but what will impact him or others in the future. However when it comes to arbitrary things like lifestyles or interests, I will support him and try my best not to limit him in his choices.