A San Diego art group invited me
to participate in a session
of figure painting. I accepted, of course, as the human figure has always been one of my favorite topics.
The model posed with her dog and we had about an hour and a half to paint. The experience was a bit of a challenge, since the pooch sat down differently after every break, but I have often considered challenges to be an artist's best friend.
Try limiting your time, reduce the assortment of colors on your palette to the bare minimum, choose an unfamiliar size of canvas, or a model in movement and you will see that, in response to these "obstacles", your attention will be more focused and your concentration heightened.
As far as time constraints are concerned, I feel that a quick, sketchy color note can say more than a perfectly rendered painting.