Because UFC 4 is all about enforcement, you are enforced to be clinched when just 1 side wanted to, same with take downs, auto converted front kick to knee along with everything else.
4 games in a row, the series is still just a broken experiment ground for incompetent dev's "big ideas" on top of a broken low quality animation pipeline which they pro-claim "da greatest combat system of all time! WAA" meanwhile the input deplay can't hardly execute players exactly input.
I guess the decline of user review from 5.5 - 1.5 taught them nothing, since they sit on a gold mine (UFC license) and EA's carefree management