Anti-Perfect
You can’t write a perfect thesis from a perfect piece of research that then leads to a perfect viva experience.
I can understand aiming for perfection and trying to make something as good as possible but working towards “enough” is probably more sensible.
You can define enough. Enough has a quantity: enough research, enough words, enough work to get ready. You can plan for enough. You can work for enough.
No corrections doesn’t mean that your work was perfect.
Enough. You are good enough. You have done enough. Do enough for prep and do enough in your viva. Perfect is a distraction and you can do better. You can do enough.