When one's sports team makes it to the playoffs. Team members stop shaving their facial hair thus growing a 'playoff beard.' As long as that team is in the playoffs, the beard stays. When the team loses and gets removed from the playoffs, or ends up winning the championship; then, the beard can be shaved.
"Hey John, I heard your team lost your semi-finals game yesterday."
"Yeah we did, it's a shame. I gotta' shave the old playoff beard off tonight."