I think most people are scared of breaking something, if they're sensible. I know a couple of people who aren't scared to 'try' anything and the result has been a semi-burned down apartment (I can do my own wiring!) and a new set of dining furniture (I can sand it down myself!).
I think that the fear that people tend to have is from ignorance though. I'm trying to learn about being my own atuo-mechanic; I'm teaching my father more about the computer. What people maybe don't realise is just how hard it is to break a computer permanently. This is one of the biggest factors in people being poor with computers; I think that another is that there is often no clear indication of partial success, which is pretty discouraging for an adult who is starting to learn.