I was chatting with some graduating seniors the other day and they asked about the ways I'd seen previous grads fall short of their potential. This is probably going to take several posts but one thing that came to mind is how people sometimes end up limiting themselves (or self-sabotaging) based on the story they have in their mind about themselves. This can take low-key dimensions: an A+ student is so used to being praised for doing a perfect job that he selects situations in the workforce where he will also be able to do a perfect job, not realizing that those situations require little growth and learning, which should be two primary considerations in work after college. Or a student who was used to getting good grades without much effort clings to assignments (or jobs) where he doesn't have to work very hard because he has no idea whether he can even succeed otherwise.
But this can also have farther ranging implications, especially given the importance of personal essays to get into college. Admissions committees often like seeing stories of resilience, and who doesn't want to be resilient, really? A student who has been able to defy the odds and overcome poverty, a single-parent family or various personal hardships had much to be proud of. At some point, though, it is important for those students who have defined themselves as outsiders to find their community and rewrite their story. At some point anyway, you realize that few people go through life without any hardships, whether those hardships happen early in life or later.
If they don't, they may only relate to, say, other people from poor backgrounds without realizing that maybe their supervisor with the fancy car has overcome much personal struggle as well, or overly focus on another employee as a father figure because they grew up without one. (While mentoring is an important component of personal growth, my take on failed parental relationships is that you never find a replacement for good parents outside the family, there is much potential for meaningful personal relationships among friends of all ages - just not surrogate parents.) They may also focus on minor issues that trigger them because of their childhood, or may be taken advantage of by people who want to get ahead without being quite technically competent for it but have the street smarts to detect weaknesses in others and exploit them.
You can tell if you're clinging to a story if (1) you bring up the same components of your past again and again to people, who gently comment they've heard this before or (2) the same things or people keep annoying you, to a degree far disproportionate to the actual offense or (3) different people keep providing the same feedback to you and you keep finding "excellent" reasons why their advice doesn't apply in your case.
If you think you might be in this situation, I'd say you should first honor the story you've told about yourself so far, because it has helped you bring you to the point you are at. Then you have to focus on changing your self-image and telling a more empowering story about yourself, to match your new situation. Pick a new affirmation, like "I relate well with all kinds of people" (instead of only connecting with only outcasts who match your story of outsider-ness) or "I display grit and resilience at work" (instead of coasting through assignments by giving them your minimal effort), and find 5 things to do each day to express this new truth about yourself. If you want to relate better to others, this might be as simple as replying promptly to an email from someone you view as the quintessential insider. If you want to learn grit or resilience, you might simply take a colleague for coffee and ask them how they worked through this high-stakes project you've been hearing about, or watch 1 video on a topic you know you should learn but don't know how. You do not have to volunteer for a make-or-break-your-career assignment this very minute. Pick 3 easy things a day, then 1 slightly more difficult thing, then 1 thing that stretches you more. And of course you can do fewer than 5 things a day, but each thing can be short and part of a bigger whole, and 5 little things will help you reinforce your behavior from different perspectives.
Beware of friends or relatives who want to keep you in the role they have known you. Often people are very comfortable with the role you have been filling and have some personal interest in keeping things the same. (For instance, if you've coasted through college, then your old roommate might want you to stay the same because he's worried about having to display grit and resilience himself and it's safer if he keeps you down in the pits with him.) Sometimes you have to loosen old ties to make progress. Finally, it helps to pick a symbol of the new story or identity you're trying to create, and keep it somewhere you can easily see it.
What made you successful in college isn't necessarily what will help you succeed after it. Plenty of outside factors explain why a promising career might get derailed: a company that suddenly declares bankruptcy, an egomaniacal boss, an important project that fails for reasons outside your control but brands you "bottom line poison" for a year - don't add your own inner issues to it.