From Diablo Wiki
"Haters" is a common slang term for people who do nothing but bash and insult and "hate on" a person or product, often one they insist they hate and have no use for (while still spending a great deal of time paying attention to it). There are a lot of haters in the Diablo community, former-fans who claim to no longer care about the game or to hate everything about it, and who make dozens of forum posts or news comments a week to make sure that everyone else knows how much they hate the game.
Haters aren't interested in conversation or debate. They've made up their minds and exist solely to try to derail conversations and ruin the enjoyment of others. Thus haters go beyond merely disappointed or bitter fans; they're out to spoil the experience and enjoyment of others.
It's often said that the opposite of love is hate, but that's clearly not true. The opposite of love (and hate?) is indifference. Hate is quite close to love, as both are marked by obsession and deep passion. Fanboys often flip into haters since both states are basically irrational points of view that are fueled by intense passion about the subject in question. It's entirely possible that today's hater can become tomorrow's fanboy, if sufficient changes are made to Diablo 3 that disaffected fans are sucked back in, such as by an Expansion pack.
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