They just didn't give him a contract.
Breaston, a Woodland Hills High School product, left Pittsburgh without an offer - or at the least without an offer he found acceptable - and will look elsewhere for a contract for this upcoming season.
Does that mean the Steelers won't sign him at all? If they do, it will be after he speaks with a few other teams, according to Ed Bouchette.
Breaston appeared immediately to be on the Steelers radar after he was released by the Chiefs this offseason. Former Chiefs coach Todd Haley, the Steelers offensive coordinator, appeared to favor Haley not just in Kansas City, but in Arizona, where the two were paired from 2007-10.
Detroit is reportedly interested in Breaston, as they look for a complimentary receiver to go with Calvin Johnson. They released WR Titus Young this offseason.
Pittsburgh will likely continue hunting for a wide receiver, though. With only Antonio Brown and Jerricho Cotchery currently signed for the 2013 season (and Emmanuel Sanders expected to pick up a restricted free agency tender offer), depth is a key concern for the Steelers this offseason.