Never enough time in a PhD to do everything you could do, but usually enough time to do everything you need to do.
Never a way to prepare for every possible question in the viva, but certainly plenty of opportunities to be ready to respond to any question that comes up.
Never a chance for you to be the best, but only a need to be your own best.
Once we get away from “all” and “every” and “perfection” in the PhD and the viva, it’s not that hard to realise what “enough” looks like.
You are enough.