Sometimes it's useful to look back on your work and deleting the maybes and the not sures means viewers only get to see quality work. Is that a good thing? 

In the long run, uploading nearly good stuff is useful in a few ways, you get to see your progression as well as the viewer. It can also plan a style which you may not have known about. 

Do I delete my art? yes I do, but only art that I get frustrated with, and deleting it means I can try it again from a different angle.