Why is sniping frustrating? How can sniping make me lose an auction if their snipe bet is lower than what I entered as my maximum?

While it does not frustrate me personally, it does seem rather pointless to list an item for several days or weeks when the actual sale takes place in the last five minutes, and to show a 'current price' which has little relevance to the final price.

Ebay might as well call it a sealed bid second price auction and be done with it.

You need to list it for a while for discoverability. Having a low price makes it seem more attractive while you browse.

  Having a low price makes it seem more attractive 
  while you browse.

I can see how buyers would find that - and by extension sniping - frustrating.