I'm not a fan of working on one painting for a really, really long time. If you can start and finish five smaller paintings rather than one bigger, longer painting, you're going to learn more.
As far as doing a scene over and over again, I know that there are people like Monet who painted the same scene over and over. So there are definitely different opinions on this, but I remember one time I was in a workshop, and I'd painted a tree one day, and the next day I thought I could do it better. So, I told the teacher that I was going to do it again, and he was a wise, seasoned painter, and he said, "Jed, you might not want to do that, because the second painting doesn't necessarily get better."
And so I said, "Well, you don't know, I'm going to do it better today." And I painted the whole painting, and it was way harder than the first one, and it turned out worse, and I ended up just giving up on it after I'd spent a lot of time.
But I think part of it is that there's something about starting something fresh, at least for me, and painting something new, even if it's just tweaking it some, or a different vantage point or something like that. It always actually gives me a little bit more motivation and incentive to begin a fresh paining.
I don't practice the same exact thing over and over again, because it gets boring to me. That doesn't mean that doing something again couldn't be useful for you, but I just don't recommend it myself.
(Paintings above are by member, Dorena Belle Petty, who DOES like to paint the same scene more than once!)
We are your home for growing and flourishing in your art and creativity. Live classes, premium courses, mentoring, and the best art community out there.