Originally Posted by Gintaras
Don't you think, if you have a lot of fragmented files and read/write heads would be flying- looking to those file fragments all over the HDD platters...wouldn't it wear out faster and cause HDD failure?
It won't significantly reduce drive life. They're made to work. Fragmentation isn't the big problems companies want you to think. There's edge and extreme cases of fragmentation where a defrag will definitely help, and make a noticeable difference, but in most cases it won't do anything. Vista started using a weekly defrag by default, and I think that's a reasonable approach. Monthly might have been better, but whatever.
SSDs shouldn't be defragged at all due to the way they operate. That'll likely /reduce/ performance, and will definitely reduce their lifespan.