Yes. An unbelievable amount. During those times, it was so much more difficult to create a realistic and three dimensional painting. They had to use real creativity and skill to complete any painting, because there was a long, tedious process involved. It would take too long to go through the whole process, but just for a short overview, they first had to project the object, scene, or people they were going to paint onto a canvas which took great care and skill using the tools of their time. Then, they had to create outlines of the focal points and backdrops using those projections. Then, they had to mix colors just right to give the impression of depth, space, and emotion, besides trying to duplicate the exact colors of whatever they were painting. All this took an incredible amount of time and patience.
Bottom line, there is true wisdom in this. Sorry if I was a bit lengthy in my response. I took a class in Art and Design History recently, so all this is still fresh in my mind.