Why do we get viruses?

Because malicious programmers write them. Their reasons for doing so vary, sometimes they want to make a company like MS look silly by exposing various security holes in their OS, and other times it's just because they are attention seeking losers who need to do something to compensate for the fact that they have never kissed a girl.

Why do we get viruses?pop up blocker

same reason we get viruses in the real world.

The need for nature to survive by infecting others %26 a large connected social network that gives oportunity.

Why do we get viruses?systemworks

wich viruses r u talking bout?i mean viruses givin u diseases or comp virus?
Because viruses surrounds us, weather they are written or produced.
what kind of virus? if you say biologically, its either you caught it airborne. or you maybe have some bad environment.. i mean theres lot of pollution. other viruses are transmitted sexually. and others are transmitted by intaking them to their system.

if its technologically. you get virus through youre emails, and by visiting such websites. people(virus writers) want to scatter their virus for some reasons

Virus writers can have various reasons for creating and spreading malware. Viruses have been written as research projects, pranks, vandalism, to attack the products of specific companies, to distribute political messages, and financial gain from identity theft, spyware, and cryptoviral extortion. Some virus writers consider their creations to be works of art, and see virus writing as a creative hobby. Additionally, many virus writers oppose deliberately destructive payload routines.

but always remember... there are also good viruses..
we get viruses through internet , e-mails , downloading software and even sometimes from vcd .
they have evolved better than humans have and they can outfox us and infect us.

Their downfall is that they continue to kill off their host when it needs to survive for their own continued survival.

They're just too good at what they do. Too good for their own good.

(I assumed you were speaking about the non-computer variety)