I almost never do any digital color on analog pieces—I like colored pencils, pens, and markers, so any pencil and paper pieces will be hand-colored before scanning. Digital pieces are constructed entirely digitally, of course. I've never been to art school, and my art is mostly a hobby, so my ways are probably inefficient/very much not industry standard, but I don't mind. :)
There probably is a noticeable difference between my digital and old-school pieces—if you're curious for examples, I made an intro post yesterday for the slothicorn community that has two of each.