This question speaks for itself. I am currently trying to complete the Pokédex in Pokémon Shield, and I have Purrloin registered, but not Liepard. So I went down to North Lake Miloch to catch the wandering Liepard there. However, when I threw my Quick Ball at it, it shook to signify it was a critical capture, but then the Liepard broke out on the first shake the ball gave. If it helps, this was after I beat Leon, so the Liepard was level 60, and was against my Level 100 Azumarill. I do not know if the EVs and IVs of the Azumarill matter, but it was EV trained and had Max IVs.

You have a 9.766% chance of a critical capture, which then has a 90.538% chance of succeeding. Failing that, you have a 67.193% chance of succeeding with a normal capture. All in all, this amounts to a 69.473% chance per ball. Thus, you have at least a 50% chance of catching it within 1 ball and at least a 95% chance of catching it within 3 balls.

Ok, so basically, if we ignore the chance of even getting a critical capture, the cat had a 9.462% chance of breaking out. This is the calculator I utilized :)

EDIT: The chance of you catching it with a critical capture is 8.84% I believe