Here is a selection of drawing I found in a moleskine from summer 2011.
I think it was around the time I took dynamic sketching 1. I had taken drawing courses at a small school for a couple of months. I remember I was quite unhappy with the sketches. At the time, I was just telling myself: "It doesn't look right but I don't know why! How can I fix this?"
Now, it's obvious why the sketches didn't work: the proportions are ok but perspective is incorrect and the line quality is hesitant. Things that can be fixed easily with enough practice with the right exercises. I didn't know that and that's what made drawing very unrewarding.
Now, after taking dynamic sketching 1 and 2, drawing has become much more tractable. When I see a drawing that sucks, I just don't think "that sucks" but I try instead to identify specific aspects that can be improved: for example, line quality, value scale, composition, lighting or proportions. And in the next sketch I try to improve these aspects. Or I can do isolated exercises to improve these area. For example, line exercises for line quality or rendering simple shapes for lighting.
That's also why critique from anyone is really important for me. They usually point me to the right area I need to develop.