I expect its very common as for most people the PC / laptop is just a tool - to write emails / play games / browse the web (hence the move to tablets).
The average user doesn't have a clue (or care) about how it works, as long as it does the job.
When it starts failing they then get the repairman in or sling it and buy another:0) Only yesterday some one commented about my 6yr old Toshiba satellite laptop saying they used to have one but it slowed down so they got rid.
Some of us are DIYers or tinkerers (see an old thread about people who have to fiddle with their PCs) and will maintain and repair our own appliances.
My wife has finally realised I can't throw anything away until I have had a go at taking it apart and trying to fix it :0)