Like many, if not most, players, I regularly use the auction house to buy and sell items that I need or want in WoW. And, like many players, I regularly experience frustration in doing so -- either I can't find what I want and/or it's exorbitantly expensive, or I can't sell what I'm trying to get rid of! I'm not sure which scenario I'd rank as more annoying -- not being able to buy what I want versus not being able to sell what I want -- but I find the latter to be exasperating in a particular way, especially if I know that what I'm selling is something useful.
I admit it: I get really frustrated when things I want to sell don't sell. Relisting is annoying, and if I'm trying to sell an item, it's because I neither need nor want it, so carrying it around isn't something I feel inclined to do. Part of it is wanting to make gold -- who doesn't, after all -- but in addition, those bag slots are space I need for other things that I don't want to sell, like transmog gear. Hence, I am forced to admit that I can sometimes be one of the people that player Kidja complains about in this forum post. If I can't get a buyer on the AH for something at the price I think it deserves, I will sell it for as under-market as I dare simply to get the goods moving.