Drawing is a muscle between you hand, brain, and eyes. I can't find exactly where this idea came from but it's often talked about to show that drawing is a skill rather than a gift. One must practice the skill and develop the muscles.
"Nothing really good happens inside your comfort zone." -Michael Hyatt said this at WDS2014 but here's a great post he has about it.
There's a disconnect between what we want and the amount of effort were are willing to put in. I think this one comes from listening to Jonathan Fields on some podcast. As I was searching for where it came from this morning, I found this great video he made about it. #iamwilling and I own the process.
Sketching and pooping are a lot alike. You just gotta take your time and relax. I'm embarrassed to admit that this thought was all mine. :)