The Buffalo Bills upgraded at backup quarterback last offseason, letting Matt Barkley walk and signing former top-2 pick Mitch Trubisky. Barkley bounced around, spending the preseason and first two months on the practice squad with the Tennessee Titans. The Carolina Panthers added him to their active roster for seven weeks when they had QB injuries but he was cut and claimed by the Atlanta Falcons, who then cut him and placed him on their practice squad.
In short, people like Barkley as a veteran backstop option, but not as Plan A, B, or C.