Additionally to info BC stated about computers for basic browsing and e-mail needs being able to get by with a 13 year old PC, many people have seen or heard about complaints about Windows 8 and 10 and they decide to stick with Windows XP, Vista, or 7.
The only driving force that causes me to have a need to stay with a system that is only a few years old technology wise is due to Video Games. If I wasn't a gamer and only web surfed and e-mail, i could potentially get by with a Pentium II 233Mhz running Windows XP for web surfing and e-mail with a Geforce PCI type video card. The flash content might run a little rough on a Pentium II, but video content that is driven off of video card vs software rendering needy of CPU processing would probably be bearable. But these days I dont bother much with use of systems day to day that are not at least a dual-core, because why deal with a laggy single core system when you have better to use.
Additionally many people are building their own and upgrading their systems as well and so manufactured computer sales will take a hit from those who buy their own parts and stretch the life of an older system or build a custom build fresh.
Lastly with all the modern android phones and tablets etc, those who dont feel a need for a keyboard have migrated over to these portable touch screen computer devices. I just finally bought a LG Android TracPhone back in August and I resisted getting one mainly because I didnt want to be like so many others out there that go overboard with the use of them, these are the people who walk into objects such as fountains in malls and you have to avoid them walking into you in public because they are walking in a direction and not watching where they are going when texting. I have to say that its nice to be able to check anything out on the web from almost anywhere, but I cant see prolonged use of it as well as I really truly enjoy use of a physical keyboard vs a touch screen and having to use backspace and correct the spell checker that thinks its helping me such as for example its not good to text to your wife that the "
secretary stopped by and we were just grabbing, I will be home shortly", when I really typed
"secretary stopped by and we were just gabbing, I will be home shortly" and the phones autocorrect for spelling decided it would be so much better for it to be Grabbing instead of Gabbing. I have also had other words that I can not share here because they are inappropriate pop into a text to a friend about Strawberry Yogurt. While it made us both lose a lung laughing so hard, it was so wrong in how the autocorrect of the portable android device handled it. And thank goodness it wasnt a text to anyone like a boss or client etc
I will have to be careful and not use gabbing and instead use talking. Thinking now of how the phone could mess up Talking to be something dirty or way wrong.