Because "fitting in" means exactly that - you fit in space that is just big enough to allow you to work and not much else. Creativity and curiosity require wandering around.

Creative people are willing to follow another's lead if they believe it to be beneficial, as in a mentor/protege relationship where the mentor is clearly superior at the craft. People who will put themselves into the total subordination that the corporate world expects (in which you de-prioritize your own progress, education, and career in favor of managerial-organizational statism) lose their creative capability and rarely are able to get it back.