I had a client that wanted airbrush painting on his helmet. I didn't count the hours I used on this, but I started before Christmas and finished it at first week of May. Why soooo long? Client said "there is no rush and no need to stress" - so I took my time and I'm clad I did.
I used to do my work really fast, within short time frame - but not anymore. I now days say that I'm not the fastest painter.