that's how it's always been done" reminds me I still let my phone charge overnight for no reason lol.

Why do you think this mindset became so common in the first place? It's like once a schedule gets written down, people stop using their eyes and just follow the paper trail. You could apply that same logic to so many parts, not just belts, and save a ton of time and cash. I guess it's easier for some shops to just bill for the whole replacement than to actually check things. We end up wasting perfectly good stuff because nobody wants to make a simple judgment call anymore.