So I've noticed that there have been quite a few artists that have gone through, or are going through an art slump or art block.
I came across this article that has a few tips and suggestions to help one stay happy as an artist.

http://skinnyartist.com/5-habits-of-happy-artists/

I also found this one, talking about the warning signs of what they consider "amateur artists". Now granted, I'm sure not everyone here is trying to make a living from being an artist, but I think there are tips in this article that can be applied to people who just want to get better at creating art in general.

http://skinnyartist.com/9-warning-s.....mateur-artist/

Particularly #5 in the first article and #7 stick out the most to me as the most helpful tip for artists wanting to get better.
I think it would help people when they receive critiques too.
You just have to see each piece you work on as a step in the process of becoming a better artist.
You can't become too attached to the piece you were working on.
Otherwise, you'll never be able to improve.

I'll keep posting stuff like this if I happen to come across it as I go along.