Why Computers sometimes crash?

because it is their right to crash..

May be your computer got very little ram.In lack of memory you can face a crash.Also try to scan your pc for spyware or virus.Because these days many new type of spyware causing crash to pc.

depends what kind of "crashes" do you mean... it depends..can be viruses[like humans] , spywares ,etc... this is the explorer platform..if you mean the compnents..hmm :-? it's hard..I mean a computer board ussually never crashes...

Computers were made pretty recently...so these computers are still imperfect. It's very probable that after a few years, deppending on the system you have your computer will crash. Its practically in the nature of pc itself. Also, I want to say that the most recent cause of crash are viruses. There are so many "species" of viruses these days that you can not avoid a crash...