1. People with a higher maximum bid will always win (it's funny to watch people caught up in a bidding war pay more than something is worth).
2. Other people using auto-bidding/ sniping software (this is possible if both maximum bids are the SAME).
3. People who are online entering last minute bids live (this is easy to do and the highest bidder wins anyway).
Last minute bidding software is fair. It comes down to a simple rule, the person willing to pay the most will win the item regardless. Doesn't matter if bid 2 seconds after the item was listed or 2 seconds before it ends.