I can’t abide the term overachiever, It’s not possible for people to rise above their level of competency. We are all in some way under achievers to varying degree.
One of my bugbears are sports and business leaders saying a person gave 110 percent. How can that be possible? Coach John Wooden only ever judged a person on how close they came to giving 100 percent. Knowing a person could never reach perfection, and that 110 percent is impossible.