sentences:  Crystal Palace's Championship play-off triumph in 2013 made them the first team to reach the top flight of English football as play-off winners on four occasions.West Ham United, Watford, Bolton Wanderers, Hull City and Swindon Town have also won the second-tier play-offs on two occasions, although Swindon have only won promotion once, as promotion was withdrawn following the first play-off victory due to financial irregularities.As well as enabling lower placed teams to gain promotion which would not have been achieved under the format of only having automatic promotion places, many third placed teams who missed out on going up automatically have missed out on promotion after being beaten in the play-offs.