Maybe some of the unused/virtually new knives aren't attracting buyers because, being unused/new, there's only a small amount of savings compared with the new prices with the vendors. This Shig and others usually seem to be discounted at 5-10% off the new price, so if it's the right knife at the right time then it's a bit of a deal. But if you weren't necessarily thinking of picking that particular knife up at the moment, then perhaps it's not enough of a deal to convince.
That's how it is with me. I don't really need anything now, but always check the buy&sell threads to see if there's something I should look into. If it's not really a big cut off the new price or a really good deal for me otherwise, then it's hard to convince myself and I feel I can wait until I decide I really need something in the future, and then pay the regular online price at just 5-10% more - or maybe in a few months another deal will come along?
Plus, I don't know how it is for everyone, but perhaps times are tough. Maybe it's also why some nicer stuff than usual has been available on buy/sell/trade recently (people have observed; I wasn't here a year ago). If you're interested in buying and see more and more nice stuff appearing, it's easier to be patient too. Sorry to say, but perhaps this has been happening a bit.
Good luck with the sale. Or maybe just keep it and don't worry so much about f-ing it up as it's your 1st single bevel. It'll probably be fine.
I keep on wanting to buy, but for me it's between a new knife versus a short holiday with my wife. What would you do?