"The ultimate antidote for perfectionism is perspective: Here's who my child was, here's who he is, and here's who he's likely to be -- I should try to stop insisting that he become something he isn't."
It's true as a parent. It's true for how I relate to myself. It's true for how I relate to other people, and what I expect of them. It's really really really true.
Obviously, when I express this, I'm going to not get it quite right, because that's just kind of how I am and I continually try to improve, but I have to be realistic about my communication skills. But if you ever talk to me about my kids, and I say, "This kid is not going to ever do X." (say, this kid is never going to drive a car), I will not parent in a way that gets in the way of that kid learning to drive a car. I will do everything in my power to help my kid get to a point where he or she can learn to drive a car in compliance with the law, safely, etc. But while I'm doing all that, I'm setting expectations for me, my family and the community we exist in so that as my kid develops, if he or she never drives, that's not viewed as a failing.
And if my kid, by some miracle, _is_ someday able to get a license and drive, that will be properly appreciated as the miracle which it truly would be.
The envelope of expected outcomes for any child should be set so that the child, with a reasonable amount of effort, can exceed those expectations and, by failing to exert any effort, their failure is not spectacular, but merely a less optimal result still within the expected envelope. If the absolute most effort the kid can expend, constantly, over time, will barely meet the minimum, and that only grudgingly, then the people around that kid have created a world of expectations so cruel that it can only be experienced as a form of Hell.
Let's do better than that.
ETA: I should add -- I usually do -- that a large chunk of my prediction about my child and driving is driven by two salient facts often not in the possession of my audience. (1) I probably would never have learned to drive if I could have avoided it (and numerous members of my extended family do not drive because they were a lot better at fighting The Pressure than I was). (2) I have a set of expectations about what our world will look like over the next few decades that suggests driving will become less and less of a normal/useful/typical adult activity. As we centralize -- for many reasons -- driving becomes less necessary, more complex and more dangerous, requiring better emotional control, cognitive ability and executive function. By the time my child might be mature enough to consider learning to drive, my child will likely have established adult routines that render driving largely uninteresting and optional. That appears to be already happening with children in general.