On the Wikipedia page for The Brian Kendrick, someone edited in an entry that claims that Kendrick was released because he "did not respect Paul’s (Triple H’s) status in the company". The message was edited into the page, but there are several misspellings and as of now, it’s just a rumor.
To try and give a little bit of insight on the release of The Brian Kendrick, Kendrick has reportedly had heat backstage for quite some time. The "nail in the coffin" seemed to be back in April when The Brian Kendrick was drafted to RAW and Ezekiel Jackson was drafted to ECW, splitting up the partnership they both had on SmackDown. The Brian Kendrick’s last television match was losing to United States Champion Kofi Kingston on RAW this past Monday night.
Just a little tidbit here, but the last reported release by WWE was on June 19 when they announced they "came to terms on the release of" Candice Michelle & Sim Snuka.