Hi Nolan:
Yes, these two are common reasons. Others are tiredness (from work) not enough rest, illness (along with meds), disinterest, and (rarely) mismatched course choice. Nonethe less it's our job to reengage students with enthusiam, excitement, activity and participation, and interesting class assignments that "command attention and focus". We have to be creative, but then, that's our job!
Regards, Barry
