Other people have suggested good info to gain nuisanced knowledge. I recommend starting with a simple fact. With enough time and/or the right conditions all storage will fail. Design your setup with redundancy. I personally had to replace 2x 12tb drives this year. I have raidz3 (3 parity drives) and a hot spare. So I just bought cheap replacements from a reputable seller on eBay and consider it part of the cost of self hosting.