This is a "Depends" Type of Question

My HD in my home PC has been running since 2006 without a single problem. So, what does the life of the HD depend on? Here are some things to think about:

1) Drives that come WITH a PC are usually matched to the PC, cooling and power supply. It's only when people start blindly adding internal components to their PC do things get out of kilter. Adding a second drive without considering BTUs and WATTS is very careless although a lot of people do that, even professionals. An example would be one guy at work upgrading his PC many years ago with a brand new 10,000 RPM drive. The drive died within a week. The replacement also died in about a week. The issue? The air baffles were not there to support the heat given off by the drive type.

2) Always on or rarely on? If you only turn your PC on when you need it, despite what people say about power on "surge", the drive will probably last longer. My always on Tivo goes through hard drives every few years but my PC is fine. Even my external drive is going fine.

3) Dirt in the PC. If you don't clean out your computer, the dust bunnies will collect inside of the case and block cooling. Broken fans can do this as well.

4) Electrical surges. Although there is a power supply in your PC it is no substitute for a surge protector and/or a UPS system. I've been running a UPS for years and we don't get much lightning here. Just people crashing their cars onto electrical poles.

So, environment has a lot to do with components of your PC surviving.

Also remember bthat 10+ years ago, we didn't use the Internet as much as we do today. More and more people leave their PCs on all the time and many have things running in the backgroud so the hard drives are always working.