I keep hearing people say that hard drives won’t last long and to always have backups. But if it is like that, that means you would have to be buying drives consistently? Has anyone ever had a hard drive work for them successfully for a decade or even more where they wouldn’t have to be buying more?
I have had many individual drives last decades at work and at home the problem is that the odds for failure are the same for each individual drive but if you have more drives the odds that YOU will see a failure increase.
It is like saying what are the odds or rolling a 1 on a 6 sided die
https://math.stackexchange.com/questions/1654073/probabilities-for-rolling-multiple-dice-and-getting-one-number-or-greater
1 16.67% 4 38.58%
So think of it like having a PC with one drive, vs having a NAS which typically has 4 drives. The more drives you have the more likely it is that you will see at least one failure during the life of the drive.