I "researched" it after posting that comment. the ABC executives said for their 3rd season they were only allowed ten episodes rather than their usual... a lot more. So no they didn't decide on their own to end it I got that part wrong.
You're joking... 3rd season started off 2 years after then 2nd season, and on their second episode they showed an offensive cancer skit. Then on the 3rd episode they said it's been 2 weeks since they've been on, and they kept on apologizing, and how they got into a lot of trouble due to it. Then on the 2nd to last episode they said that they were cancelled and only had one more episode to go. Either you were drooling off sleeping the entire time or just stupid not to notice.