I would like to throw in my 2 cents of advice of what I think makes a good webcomic. First of all you have to work out a good plot and character backgrounds in advance. Secondly you should make sure that your either going to work on the webcomic yourself or have other artists help you and make sure you and them have time to work on it. Always keep updating your comic(s) frequently atleast once a week even if no ones visiting. That way if you do start getting fans they know your webcomics not dead because most people even if they like the webcomic but it hasnt been updated in awhile, they wont stay or return to it.
Thirdly don't criticize your own drawing abilities too much because that can interfere with your confidence to continue producing. Accept yourself before even starting because if you even have an ounce of doubt its gonna screw you over. It's ok to criticize yourself a little bit, but don't over do it. Also make sure you have a steady storyline so as your fans wont get confused about whats going on, like if its an action comic keep the plot steady, but if its a comedy it should have atleast some sturdy base to it and not just be random events (even though I do that with mine).
Well, thats all I can come up with for now since it is very late here (1:00 A.M.) I will continue to edit and modify this post in the future.