>>36073438Capture isn't just one random check with a fancy animation thrown on like slot machines, it's actually four checks (or three in Gen V, for some reason). Each time the ball shakes, the game performed a check and it succeeded.
A critical capture is just a special bypass in the function that makes it so only one check is needed. You can still fail the check, it's the exact same odds as getting the ball to shake once on any other capture.
