If you're perfectly qualified to do something, you've already outgrown it
My father worked in a highly technical space. PhDs only. Many of his friends and colleagues did the same thing. They were all immigrants who studied hard, got top grades, and achieved the peak of educational merit.
Career growth was a different matter. Entry into senior membership of technical staff was a distant reality for most. Every time an opportunity would come up, my father would try while the others wouldn't bother. Over time, my father began to separate from the pack.
One night, out of curiosity I asked him why. He explained that many of the others were just as qualified as he was at the time. But when those opportunities came up, they faultered because they didn't think they were good enough to make it. If they didn't meet the exact qualifications, then wouldn't they get rejected out right? Trying was a hopeless endeavor.
My father had a completely different perspective - here was something worthy to try for, something he could grow into. This singular shift in perspective gave him confidence to try where others wouldn't dare. His perspective boiled down to a simple rule - don't do things you're perfectly qualified for. By the time you get it, you'll have already outgrow it.