I do 100% of my own work on my bike (and some work on bikes for friends and family). I started with my Dad's help (some) back when I was about 10 or so, perhaps earlier. Building wheels, truing wheels, lubing, etc. Not a lot of "scratch builds", but got a bare frame build under my belt this winter, and have a couple more in progress. Shortly I'll do a build starting with bare tubes... Hmmm, I did do a SIGNIFICANT modification of a bike frame last year too.

The only thing I can remember not doing was I broke a steel bike rack near a small town in the middle of Italy 20 years ago, so I had it welded so I could finish my trip.

I'm not always the most proactive with the work on my bikes, but I get them done as needed.