It would be nice if the controller kept track of how many times each tool holder position was involved in a tool change. Then when the screws break or you replace a fork you could record the count and reset it. After a while you get a pretty good idea how many tool changes screws and forks will last and then you could do a preventive replacement once you get beyond ~ 90% of the cycles you have determined.

I am sure it is a bit more complicated than just that. I imagine that a tool holder position dedicated to a 2" face mill will fail in fewer cycles than one with an engraving tool in an ER16 collet. But that could be accounted for.

bob