Adding more to my thoughts about learning from our mistakes.
Let me put it another way about learning from errors.
If you miss an 8-ball in practice, what did you learn? You didn't even think about it again, do you? Do you think that missed shot will ever cross your mind again in the middle of a tournament match? I'd bet not (and I'm not a betting woman).
If you miss an 8-ball on the hill for your team, I guarantee you will learn why from that 100 times over.
And then carry that learning experience into future situations.
You will think about that missed shot a lot. Not because it haunts you (well, maybe at first lol), but because you will think about it enough to figure out why you missed it (and how to solve that for next time). You didn't stay down, your adrenaline was racing so you were shaking, you rushed your shot - all those feelings do not come up during practice. All those feelings only come up during intense, real-life match situations; NOT practice.
And then you learn to tame those feelings so you CAN sink the 8-ball in a crucial, future match.