Yes this and also scrubs and smart tests. I have 6 14TB spinning drives and a long smart test takes roughly a week, so running 2 at a time takes close to a month to do all 6 and then it all starts over again, so for half to 75% of the time, 2 of my drives are doing smart tests. Then there’s scrubs which I do monthly. I would consider larger drives if it didn’t mean that my smart/scrub schedule would take more than a month. Rebuilds aren’t too bad, and I have double redundancy for extra peace of mind but I also wouldn’t want that taking much longer either