User blog comment:GreenSkye/My Thoughts on Game Mechanics/@comment-209.161.170.138-20121026215519

Backdooring only worls if they don't catch on. If they are stomping you so hard in teamfights, that also means that if your team is down a person while you're backdooring, the enemy team can just straight push into your base, and if they're dominating you in teamfights, I'm sure that 5 of them can push faster then one of you.

Securing an ace to push is a much safer bet. Not saying backdooring never works, but to use that in favor of actually fighting and getting an open push is just plain dumb.