The cardio issue. Many of the guys on TUF can't afford to train and fight full time and because of this they are not high level UFC caliber athletes. That is to be expected and is really unavoidable. Smaller guys though generally have better cardio which means they don't gas out as easily. That makes the fights look better on TV especially to people who are channel flipping and without a lot of reference points they likely don't realize they are smaller (the UFC uses a smaller cage for TUF).
Also please don't double post, if you want to add something edit it in.
"If you get hit and it hurts hit him back you not knocked out yet."-Joe Doerksen
The Toxic Terrors (FFL)
Demetrious Johnson*Eduardo Dantas*Emanuel Newton*Will Brooks*Michael Page