When nearly everybody runs software based on a very similar codebase, a piece of malware that takes advantage of a base configuration / service can spread like crazy. Much like in nature where if everything is too genetically similar a single virus or disease can cause widespread devastation.
Most software to protect computers is based on yesterday's threats, and since there is way more money for individuals working on the dark side than the light side, the light side in this country is always one step behind.
The biggest problem is most people don't actually care all that much, they just want something easy to use, something they don't have to think about, happily giving up control of their data, their livelihood, their friendships, their intellectual property to some big corporation who promises them a few freebees.
"Microsoft Windows" and the whole surrounding ecosystem of office / outlook / flash / java etc. is one giant mess of security holes because of a problematic base where it basically says yes to everything unless you have said no or it has a rule (patch) to say no. Why is your e-mail client able to be hijacked to run files from e-mails? etc. It was built to be easy for the average person to use with security as a secondary thought.
If you want to take control a bit more, then learn how to run multiple alternative operating systems on your computer, so you can pick the one you want and be able to re-image it if needed.
Have a e-mail address that you actually control (if running an e-mail server or domain is too much for you, at least have a couple good ones that you pay for with your ISP)
Have proper physical Read only media backups of your important files & make updates regularly.
Of course Microsoft, Apple & Google all have a "solution" for you... give up all your control to us, we'll keep all your data, only run things you buy from us, with only our special locked down OS and only run programs that you buy from us.... still helps little with all the back doors.... oh and keep paying forever with your money or your personal information.
If you care about security & freedom, You should really look into having at least 1 computer or at least one boot setup for your computer with an OS you can control such as Linux, BSD etc.
