No one can be who they want to be. This is what I'm saying for those who are always striving to achieve better.
People's character is shaped by their behavior. Education and environment play a significant role in character formation. If a bad person has five good friends, that bad person will change over time. Conversely, if a good person has five bad friends, that good person will turn into a bad person over time.
Better is nearly always possible, but we always want more.
Get surrounded by better, rather than being the best of the worse.