Why so many headphones for sale with less than 10 hours of listening time?

A lot of people just aren't headphone people, they jump into the game and still listen to there main rigs as their source of music and the headphones just sit,then they need something for the main system and sell off unused gear to make the purchase. You mentioned Audeze as one that gets moved with low hours and I noted that as well when I purchased a pair of the 2s from a guy that was moving up to the 3s. Toyota has sold a shitload of Cambrys so it would make sense that there would be a lot of them in the used market.

Sense62, to address the issue of comfort on the Audeze, I have really enjoyed mine quite a bit over the few months that I have owned them and have used them hours on end with no issues with comfort, I use them with a Yamamoto H-2 tubed headphone amp that is very impressive in it's own right. Let me also say that I do not consider myself a headphone guy but did want a really good set in my retirement system for future reference and listening. I used the forums and reviews to choose the Audeze but I am sure there are a lot of other flavours in and around their price.