Because all bidders have the ability to place a MaxBid, you may find from time to time that you have been outbid by an amount that does not seem correct.
For example, if your MaxBid was $100, yet you lost an item to another buyer who won for $101, here's why:
At 12:01PM, the Lot 1 is at $35.
At 12:30PM, Bidder1 (yourself) places a MaxBid for $100.
Bidding continues and at 12:45PM, lot 1 is at $86.
At 12:46PM, Bidder2 places a MaxBid of $101.
Bidder2's bid is accepted since it is above the $5 minimum increment at the time (since the lot was at $86), and it also outbids your bid of $100.
As another example, if you place a MaxBid of $15 when lot 2 is at $5, why did the bid jump to $13.50?
The other bidder had a $12.50 MaxBid which is why when you put in the $15 MaxBid, it jumped to the next $1 increment from the $12.50 MaxBid to $13.50.
Note: Increments are only used to calculate the minimum bid amount. If you submit a Max Bid on an item that already has a Max Bid by another user, then the user with the highest Max Bid wins.