Brian Kendrick was released from TNA Impact Wrestling due to budget cuts in regards to talent established over the last year.
When Kendrick returned to TNA in 2010, the company was spending a lot of money to bring in former WWE guys preparing for what ended up being their failed "Monday Night War" attempt. I'm told Kendrick was making four times as much per match as some of the newer X Division guys that have been brought in over the last year.
The pay scale in TNA has gone way down, especially for the X Division and Kendrick wasn't willing to take a drastic pay cut the company was offering him. This is why he ended up parting ways with TNA.