Although there are audiophiles who are obsessive about keeping equipment like new, there are a sufficient number of audiophiles who are not. I question sellers very thoroughly about condition, and have been told the unit is mint, no scratches at all, and then I get the piece and there are scratches and little nicks on the unit. This irks me to no end. If as a seller you are asked to LOOK for cosmetic flaws, and then you claim there are none, when in reality there are, you are dishonest. I think it boils down to two things: (1) the seller is afraid to disclose small flaws, fearing he will not get his price or sell the item; (2) the seller is not a very fastidious or careful person, and does not know how or even care how to examine a unit.
As a seller, I try to accurately describe my item, and if asked specifically, will detail to the buyer with a fine tooth comb everything about the piece. Sellers will use the excuse, "it's used; if you want new, buy it from a dealer." Sorry, that's a copout. There are audiophiles, like myself, you keep their equipment in brand new condition and pride themselves on doing so.
There are other situations, like noisy tubes, or other subtle problems, that I have encountered enough times. The excuse is always that "I didn't notice it," or "It didn't do that when I had it." Sorry, I don't buy that. Furthermore, as a seller, it is your responsibility to check your unit thoroughly as to its mechanical/ electrical condition.
How many of the Disputes in Audiogon's Dispute forum have this type of problem? A lot. Sellers try to get out of what is clearly their responsibility by lying.