Not necessarily i ran my computer 4 years without a single problem it more so has to do with the user itself and their basic knowledge for example when download from sites that have a automatic installer it would be more wise to do otherwise get a program that automatically disables the programs that include this ad-ware yes there is the odd chance you take a risk and get something like a Trojan rogue antivirus but there is always ways to get rid of theses without the detection if you have a general understanding of where most virus write there code you are write a general consumer would be smart to not run windows without a basic anti virus and anti malware program