Unpopular opinion: you should test your shutoff valves before you need them
Last Saturday I went to swap out the faucet in my upstairs bathroom and turned the shutoff valve under the sink, only for the handle to snap clean off in my hand with water still running full blast. I had to run down two flights to the main in the basement, and by the time I got back up there was about an inch of water soaking into the vanity and the hall carpet. Turned out the valves were the original ones from 1988 and had basically fused shut from years of hard water. I ended up cutting the pipes and sweating on two new quarter turn valves, which took maybe 40 minutes once the water was off. Now I go around once a month and just crack every valve open and closed a quarter turn so nothing seizes up again. Cost me $12 in parts and a ruined $60 bath mat, way better than a burst pipe at 2am. Does anyone else do a valve check as part of their normal upkeep, or am I overthinking it?