Well with a terrible second season that had no focus, eschewed character development and no decent plot lines, no show is going to last no matter how good of a start it had and therefore, Heroes fell. It would seem that the untimely disruption of the writer's strike that was taking place, played a part, finally bringing what could have been one of the best shows of the decade to its knees. Eventually this sum of negatives took its toll and with only a slightly improved third season, we all knew it was too late for any hero to save this show.
Redemption could be on the cards people! Heroes will be returning in a 13 part spin-off feature.
RIP Heroes 2006 -2010
The Rebirth: Heroes Reborn: 2015
One note for the writers and producers - STOP killing off the most interesting characters!