I changed careers at 34 after working in food service and starting my own restaurant. I decided this "Internet" thing had legs and started teaching myself. Got a job where my boss realized how little I knew, and paired me up with someone who has become my best friend and mentor.

Before the switch, I was used to working insane hours, and I had little money (due the failed restaurant). So I was hungry, no family to support, and in a perfect situation to go for broke.

Today? I could never make the same changes. Supporting a family, and a wife with a career of her own. A mortgage, and retirement in a decade. All these things limit the amount of change you can (or are willing to) take. So I put my curiosity into hobbies etc.