Why did Marion barber retire?

Answer 1

He apparently had had enough of pro football. Marion Barber III, who played for the Dallas Cowboys from 2005 to 2010 and the Chicago Bears in 2011, announced his retirement on March 23, 2012. The announcement came the day after the Bears signed free agent running back Michael Bush.

Although he had several productive years with the Cowboys (highlighted by his selection to the Pro Bowl after the 2007 season), Barber's 2011 season with the Bears was something of a nightmare. He missed the first three games of the year because of an injury. Later, he was pressed into service when Chicago running back Matt Forte was sidelined.

Barber made several critical errors, including two key mistakes in a December game in Denver that enabled the Broncos to beat the Bears in overtime. With less than two minutes left and the Bears clinging to a 10-7 lead, Barber ran out of bounds when the Bears were attempting to run out the clock. As a result, Denver regained the ball with just enough time for quarterback Tim Tebow to lead the Broncos to a game-tying field goal. In overtime, Barber lost a fumble, which enabled Denver to kick a game-winning field goal for a 13-10 victory.