The Definition of a Phrase

[MaryAnn]

Don't Burn Down Your Bridges Behind You

[hal]

Well if you have burned them down you can't go back over them can you? So it means don't put yourself in a position you can't retreat from

[melv]

Exactly, for instance if you are leaving a job due to getting a new one, don't on your last day punch your boss and wipe all the drives etc you never know when you may next bump into someone, or worse, need to go back to your old job ;-)

[Tioc]

Military origin. No matter how well you are doing and how confident you are don't over-estimate your abilities and cut off your avenue of retreat if things go bad. Basically don't get into a "point of no return" situation.