People can always learn and grow; not upward physically perhaps you can't be that 6' person, but you can change how you view the world which makes up the lion's share of mental "disabilities". If you do a math problem wrong, you can go back and find the mistake and do it right; if you drop a stitch in your needlework, you can go back and pick it up. Behavior is all learned and can be changed. Sure if you do something you deem "wrong" for 30 years it's not going to get corrected in six sessions of therapy or your money back! Behavior causes habits and we know how hard it is to stop smoking or any other bad habit? There are association threads that bind one to the behavior. Same with anything else we want to change.