1. what motivates you to leave comments on webcomics?
Something unexpected happening, really good art, the comic just generally being good.
2. why do you hesitate and do not leave a comment?
A lot of the time I just don't have anything to say. Or maybe what I wanted to say has already been commented. Sometimes I just don't have time because I'm on the go or working or maybe not enough happened in the update for me to comment. Especially if it's just a one page update.
3. what types of comments do you usually leave: emotional, supportive, constructive, theory crafting, etc
I like to compliment creators on their art and/or writing. Just generally encourage them, since they're working for free or very little.