The UFC roster is quite large nowadays, and the reality of fighting dictates that sometimes fighters aren’t performing well enough in the Octagon to stay with the promotion. 10 of those fighters are no longer on with the company as of today.
Two of the more prominent fighters were guys with eight or more UFC fights under their belts. One that was already confirmed in the past was veteran welterweight Sergio Moraes. In 14 UFC fights he was a very respectable 8-5-1, but he had lost three in a row. Another was Zak Ottow, who went 4-4 in his Octagon appearances. He alternated wins and losses his whole time with the organization, but was stopped by Alex Morono in his last outing.
Here are the other eight fighters who are no longer on the roster (via MMA Junkie):
Boston Salmon (6-3, 0-2 UFC)
Allan Zuniga (13-1, 0-1 UFC)
Darrell Horcher (13-4, 1—3 UFC)
Lauren Mueller (5-3, 1-3 UFC)
Jason Gonzalez (11-5, 1-3 UFC)
Kurt Holobaugh (17-7, 0-4 UFC)
Te Edwards (6-3, 0-2 UFC)
Rostem Akman (6-2, 0-2 UFC)
In addition to that, it appears that heavyweight Allen Crowder (10-4, 1-2 UFC) has decided to retire from MMA and is no longer on the roster as well (news via BJPenn.com)