This depends on the system. Mechatronics engineers spend a lot of time learning and figuring out how to make systems that can withstand edge cases like an incorrect screw size. There's whole engineering/mechatronics disciplines around automation reliability (though much of it involves lots and lots of sensors and cameras, haha).

The way they test these things is by intentionally throwing bad parts into the mix at various stages of their automation. Something like a screw being too big/small is a trivial matter that won't make it through a system or facility designed by professionals.

The real problem that really throws a wrench into every mechatronics engineer's carefully-planned automated masterworks is people doing things like throwing wrenches into their carefully-planned automated masterworks 😁