BIN are a waste of time, as nobody uses them on high value items. Everybody looks at the bin price, and when it's still there 3 days later, people think "Why is nobody else buying it?"
That's a good point, and this is a factor, BINs can sometimes miss potential, but they're not a waste of time. After a fair bit of trial and error I've found that overall they work better for me. Your mileage may vary obviously.
Sometimes people get carried away in auction and bid above a BIN price elsewhere, but sometimes those people don't actually pay. I got to the point where I'd dread the outcome after an auction went surprisingly high. 0 feedback winners shit-bidding or pulling return scams. This is so frequent in high ending auctions. Completed listings don't show you that, and they can't be taken too seriously.
Almost exclusively now I use Buy it Now, immediate payment required, no offers (offers just beg people to delay purchase, start a time consuming barter and then often never return). I got sick of auction winners (if not outright trying to scam me, then) changing their minds or asking for time then disappearing. It happens a lot and when it does it damages your next listing when viewers assume something fishy.
With BIN things sometimes sell fast, sometimes they sit for ages with curious non-buying watchers as you say, but they eventually sell if they're at the "right" price. And most importantly of all, the buyers are forced to actually pay. This is just what works for me and my items (mostly Japanese console games). I think with niche items that only have a handful of watchers at a time, the risk of auction outweighs the potential of luck.
