Masterbation (and porn) is not morally wrong. There is nothing sinful or evil about the human body and sexual desire.
But the consequnces of ejaculation are actually pretty severe for a guy. The rewards of giving it up are great. As in, life-transforming. And fortunately, you don't have to give up sexual pleasure to reap the rewards of not ejaculating.
Any man reading this and wondering what I'm talking about, I would seriously advise taking the time to watch the following videos:
http://www.reuniting.info/resources/videos_on_sex_without_orgasm| Reuniting
And for those with undeserved guilty conciences regarding porn, this could help as well:
Help! Porn Addiction in Progress | Reuniting