You don't get good at anything merely by being passionate about it; dedication is still a pre-requisite for virtuosity, regardless of how innately talented someone is.
Passion should then be defined by the propensity to put in the work necessary to get from A to Z.
But then there comes to problem of facing failure. Even geniuses face this problem. That's because when we're passionate about something, our basis of comparison isn't who we are, or what others are capable of.
Instead, when we're passionate about something, our basis of comparison is who we can possibly become. That comparison means that when it comes to judging our own work, we usually give ourselves a big, fat F.
The smarter you are, the more you're going to fear mediocrity, and the more you're going to be critical about your flaws.
We can discuss about the negative impacts of this, and ways to deal with this another time, but do acknowledge it's there. After all, that's the first step to accepting this idiosyncratic inadequacy, and turning it into an ally worth fighting for.