Why Does The Computer Sometimes Fail?

Computers are very complex machines with increasing numbers of parts. This all leads to an increased chance of computers failing. We wil split failing into two different parts: Permanent fail and just cashing.
Permanent fail means that your computer is broken and will not be working again. This can be caused by a number of factors and issues and can mean that your computer will have lost a number of files. Make sure you back your computer up regularly to prevent this from happening.
Computer's crashing is a far more common and far less fatal thing. Computers crash if there is a slight issue with a programme or it meets an unpatched part of the programme. Sometimes they crash when they get overloaded with requests for information. In fact there are a huge number of reasons for computers crashing.

• One of the most fatal of these is because of a bug or a virus in the computer. This should be prevented with the use of a virus protection programme or some sort of PC protection. This will limit the chances of you getting a serious problem on your system

• Computers can also fail if there is a physical problem with the computer, for instance if someone breaks it or bangs into it. Computers are delicate machines and a knock can cause them to fail. Be careful of them and try and prevent banging them or spilling liquids on them.

• One of the other ways a computer can fail is if it gets a shock through a phone connection during a lightning storm, this can destroy a computer and fry its insides. To prevent this unplug computers during storms ad ensure you have a surge protector.

There are virtually a lot many reasons. Top three are as under

1. No virus protection.
2. Spyware,Malware,Hackers.
3. Hard drive failure.
   

Well there could be many reasons for this just like nidar said. Someone very common ones are your computer has a virus or something has gone wrong with some of the parts!

Reason of computer system fail to function

Errors in instructing a computer?