Each person thinks they have a special purpose.
A natural drive for their ambition.
What separates the successful from the normal are their opportunities given to them by others and their will.
A strong, carefree, will allows you to be happy during the transitional periods of your life, but a strong will coupled with high expectations for yourself can be crushing. You must always strive for your dreams, but do so with the concept that you may fail. Not everyone is given the best odds. All you can do is hold in there and hope your opportunity arises. What these people judging themselves must realize is that there is nothing wrong with being normal. You can push, and strain for a goal and never have it come to realization. Maybe not because you don't possess the skill, but because you have never thought of the fact that we don't all get lucky and the world runs on average Joes. Pounding out paychecks for just enough to live and get by with an average life. One must never, ever, give up on what they think they are meant for, but to focus on only that is naive and self-appreciating. Sure you feel like this is your time, your place of purpose, but so does everyone else. Don't go putting yourself down every time you fail. Failure is to be shrugged off, not mourned over. Being angry with yourself only makes you not want to try anymore. Or it makes you try so hard you lose focus on the rest of life.
If you feel disgusted with yourself, or ashamed, then you need to throw away your pride. What makes you better than anyone else stuck in the same place as you? Sure you may be smarter, maybe better looking, more physically in shape, but on life's playing field luck is the usual decider of the game. The luck of the draw at that, because most are born into their social and financial settings.
And for those who absolutely have the means to do great things but would be happier being average, be average. Stop living up to everyone else's expectations, or even your own. Live up to the expectation that you will be happy. You don't have to be successful to live happily. You just have to be alive and doing what you want to do. Or at least pursuing it. Doing what you hate will just make you stop caring about life at all.
Take your little moments out of life and hold them tight. Because you really aren't all that special.
There's a couple million more of you, thinking the same thing.