I graduated high school with a 3.29 GPA. And college with a 3.10 (I think). I was a solid "B" student (Actually, I suspect I was more like a C-student, but with grade inflation, you know...).
Honestly, I can't believe I did even that well. From junior high on, I rarely completed my homework without the "help" of others. When teachers would ask for a 5-page paper, I'd turn in a 3-minute movie. My senior year I spent more days May-June in the ocean surfing than I did in school studying.
But being average turned out to give me a real advantage later in life.
See, I was a master of nothing. Not naturally good in math, science or really anything else, I learned to learn "enough" and solicit help from others who were good. Who were naturals.
This taught me three big skills:
1) How to be a generalist. A person who is able to juggle bits of knowledge of lots of things without mastery of any of it. As a result, I learned to pull on wide-ranging experiences and data to create new ideas, to listen, to ask questions of people who know, and to challenge the norm.
2) How to work hard. When a specific gift doesn't come easily to you, one is forced to learn how to work hard in order to keep up -- which, in the long run, often leads to becoming better than average.
3) How to take. You can't just wait around for others to give you a title or responsibility or mission. You have to reach out and take it. Or make it yourself. Otherwise you'll spend a lot of time doing a lot of nothing.
Today these skills, gleaned from years of average-ness, are actually in-demand. They can add value to companies and individuals who are over-worked, over-stretched and over-stressed and simply need somebody to relieve their pain.
Obviously, this world desperately needs specialists. (Not sure I can even identify my car's valve lifter, let-alone repair it/them).
But if you're not a natural specialist, don't fret, perhaps you are a natural generalist.