I've painted off and on for about 35 years. I'm still mediocre :). Granted, it's more about getting them on the table than producing quality. The times I've really taken a lot of time and done multiple layers of washes and highlights, they looked pretty good, but not as good as what @FacekicknInc showed. The resources back then were harder to find, I've learned a lot about simple ways to add a lot of depth in the last few years. So much knowledge out there and great videos.