Your career and your life will grow from self-leadership; not your boss, not your family, not your industry, not your job, not your circumstances...YOU!
That's why it's key to spend the vast majority of your time leveraging your strengths. If you only focus on your weaknesses, you are going to end up a very average person.
You are never going to be a "goto" or guru in your "C" subjects, but you can be one in your "A" subjects. In the real world, the "gotos" make things happen...not the people who made sure they "covered all the bases" on their report cards.
Knowing a little bit about a lot of things is obsolete - we have Google now. I can learn a little bit about a lot of things within one minute, anytime I need or want to.
But if you have a deeper knowledge about one or two things, THAT sets you apart. That is what makes people remember you, hire you, refer you and then hire and refer you again!
Knowing what you are good at is number one.
Number two is giving yourself permission to do it!
Number three is doing it!
In what area do you have some talent, ability, AND enjoy growing consistently? THAT is insight into what your true value is.
"Believe in yourself! Have faith in your abilities! Without a humble but reasonable confidence in your own powers, you cannot be successful or happy." (Norman Vincent Peale)
YOU need to be self-aware and honest with yourself. This is about moving you forward and thriving, not about beating yourself up about what you don't do well.