Even though they used a sniper, there just wasn't any demand. I've used a sniper for many years, but frequently get outbid. While a sniper can get you items cheaper, if there's demand for that item, then you need to place a high enough bid to win it. Typically, I'll figure out what I'm willing to spend, and enter that amount. When I lose an auction, it's usually by $1 or $2, whatever the bid increment is. If I really want something, I'll make my bid what the item is worth, not just what I'm willing to pay.
For some items, timing plays a big role. I sell some items that I make, and can go weeks with listings ending with no bids. Then I'll sell 3 in one week.
I've also found that most "watchers" don't seem to place bids, so it's not necessarily an indication of whether or not an item will sell.
And lastly, I've found that more people seem to prefer buy it now, rather than bidding.