Avoidance behavior, a form of neurotic thinking, is damaging in the long run. For example, in the world of fitness many people are self-conscious when it comes to their weight or body shape or size, or fitness level, so they avoid situations where they might be judged or they might receive feedback they don't want to hear.
Examples could include someone wanting to go to the gym, to go out to socialize, or to go to the pool or beach, but avoiding these situations which cause them anxiety. Avoiding going to the doctor when you know something's wrong is another classic example of avoidance behavior.
If you want to achieve a goal, avoidance behavior has to be recognized and overcome. In reality, avoidance behavior is the manifestation of a large and fragile ego. By avoiding, we create an unreal world with no feedback about how things really are.
Instead of avoiding feedback, you should actively seek it out. Instead of avoiding the truth, you should look for it, even if it's hard to swallow.
Unfortunately, modernity has created a "safe" world where it's easy to avoid, rationalize, hide, and procrastinate. To achieve any goal, have the courage to stop hiding and stop avoiding the truth. Seek out feedback and then make the changes you need to make.