I couple of writer buddies and I were discussing some old fantasy novels we had liked when we were teens. I mentioned that I remember liking them but that I had always wished they were a little more realistic. Another mentioned that he still liked them. The third said that he had re-read them as an adult and they were just plain bad.
This got me to thinking about books that are supposedly bad. Yes, to our adult minds such books may indeed be bad. Yet does that qualify them as a bad book if in the taste of teens they are really good? Many of us might argue that yes they are bad, but publishing is a business -- if teens will spend money on books that we adults will sniff at, well that still makes them money-makers.
I wish agents would consider this more often when it comes to certain types of fantasy, such as traditional high fantasy, where almost all agents and publishers seem burnt out on anything that resembles Tolkien or Dungeons & Dragons in any way. So what if you think all such work is derivative? If teens and old-timer gaming fans will shell out the bucks for such books, you should be picking them up. One person's 'bad' is another person's favorite type of book.