Many people are not optimizing the videos at all, let alone adequately optimizing the videos for the keywords!
There are too many videos being thrown together that provide no real value to the viewer. Make sure the content you are providing will leave the viewer with information they didn’t have before and have them wanting to come back for more.
You would be amazed at the number of videos posted that do not have a specific call to action. Make sure at least on the last slide you tell the viewer specifically what they should do next and how to do it.
Consistency is lacking. Posting videos is a lot like posting on a blog, if you do it consistently the reader/viewer can expect to be able to return regularly and get new valuable information.