Don't have a backup plan

I'm still working my way through Seth Godin's Linchpin and came across another good idea. Don't have a backup plan. If you do, you could give up easily on your idea because of the backup plan. You know you have a fallback position, so you fall back instead of fighting. Rather than having a backup, keep pushing on your main plan until you are either successful or you truly fail, and if you fail, learn from it.