If you are bidding on eBay, there are justifiable reasons to retract a bid. Check on eBay's site under bid retraction.
I have seen auctions where a bid was retracted for the reason that the bidder "accidentally" entered the wrong bid when he obviously did so to try to find the reserve price of an item, and eBay let this stand.
I AM CURRENTLY BIDDING ON A SVP CAMERA WHICH ENDS TOMARROW IN THE EVENING, I DIDN'T COME ACROSS THIS SITE UNTILL AFTER MY BID BUT NOW WANT TO CANCEL IS THERE A WAY TO WITH DRAW FROM MY BID??? ANYONE HAVE ANY INFO PLEASE...THANKS