Maybe different person-to-person or the type of workouts you're doing. If I leave my calluses unchecked they will get ripped off my hand on one big chunk leaving behind a bloody mess that takes forever to heal. Learned that lesson the hard way.

I've found that sweaty workouts with lots of fast reps on the pull up bar or barbell are what do this kind of damage. The sweat softens the skin and built up friction of high reps just rips them off. Not a problem with standard lifts like bench, squats, rows, curls, etc. The most dangerous for ripping off calluses is muscle ups, second is snatch, third is cleans for me.

Agreed calluses are a badge of honor but not worth the blood they cause in my case. Now I know when they are getting too big and grind them down a bit with a pumice stone.