Most artists are very solitary creatures. I heard it explained once as this: we hide out in our studios for days or weeks - sometimes even months at a time, only coming out to show off our latest creation to our spouse or friend. After their initial gasp of admiration, we head back into the studio for another extended period of isolation.
Although isolation is an inevitable part of being an artist, we should seek opportunities to be around other creative people. Doing so can improve skills, diminish procrastination, and enhance creativity. Belonging to a group of artists that meet regularly to critique each other's work and provide encouragement and inspiration is greatly beneficial to all parties involved.
The most creative and productive periods of my life were the times when I was involved in some sort of organization that made collaboration with other creative people necessary. Whether it was at my job, at school, or in an independent group, it was always beneficial to me to be part of a group of artists all striving for the same goal.
I would encourage all artists out there to join or start a group that meets on a regular basis to provide feedback, encouragement, and inspiration for each other. Not only will you be more productive and improve your skills, but you may also make some very lasting friendships.