I can't see anything wrong with pornography per se - it's such a vast field; from Greek vases via the lubricious works of Rembrandt and Turner to the cheesey joyless stills and videos of today. Human beings have always been fond of the erotic, and that's a healthy thing.
Most people, however, would object to pornography which was, as Morticia said, abusive or exploitative. There's the rub (as it were); a heck of a lot of pornography these days is abusive or exploitative.
Even "straight" porn tends to be made and distributed b fairly dodgy characters (in the UK at least), and having known some people on the fringes of the skin trade, I can say that many of them feel that participation in the hardcore porn industry (as opposed to the old-fashioned 'glamour' side of things) is little removed from pornography and few of them feel happy at having done it.
Maybe that's the reason for one of the biggest turn-offs with modern pornography - everyone looks either so darned artificial or just plain bloody miserable.
If your sexual imaginiation relied on pornography to fire it up, it would be a terribly joyless (and lonely) business!.