When I watch anime, its always I have no expectations about it whatsoever because I’d like the anime to come to me naturally and enjoy it. Somehow when I have expectations of an anime, I tend to enjoy an anime less and tend to nitpick on it more which in my opinion kinda ruins the pleasure of anime viewing.
When viewing something that I’m very familiar with the source material, I tend to enjoy the anime to the fullest and tend not to nitpick so much when comparing it with the source material (unless the anime in question was a real bad adaptation of the source material, which is very rare). There are people who nitpick so much about an anime being not faithful to the source material (read: fanboys) and bash such anime at every turn for being not so faithful to the source material. I find it amazing that such fanboys even exist. Personally, I think it would be more interesting if an anime adaptation would have a few differences from the source material rather than copy-pasting everything from the source material.
In the end, I watch anime simply just to have fun and enjoy. I’d like to ask you dear reader, do you watch anime to have fun or to critic what you watch? Isn’t anime was supposed to be a medium of visual enjoyment?
When I watch anime, its for my own enjoyment. I watch anime to have fun. It always had been that way for me. I watch anime for personal enjoyment and to relieve stress.
Kuro's anime ramble blog 
Although I agree most anime just want to entertain, there are most definitely a few out there who want their audience to think about what their watching and and critique on the themes presented and such.
Nonetheless, I can agree that I don’t try to nitpick tv series, I want to enjoy watching, but sometimes you can’t help but notice the problems in a series when you’re watching it. Same goes for when I see anime from manga adaptations. It’s hard not to compare in some way or another, but I do agree I don’t mind when an adaptation doesn’t follow the source material perfectly.
I like to review the anime I watch, so it’s hard to watch it only for the reason to enjoy it. Though, for the most part, I can enjoy and have fun watching a series while at the same time critiquing it.
Comparing anime from source material is okay, but when comparing becomes too much nitpicking and starts attacking the anime (e.g. – how fanboys attack SAO anime for being not faithful to the source material), I think it causes problems because it might ruin the viewing of the first time anime watchers rather than letting them be curious enough to read the LN out of their own initiative after watching the anime.
I just watch it for fun. Entertainment is the only reason to be honest for me, and as long as its entertaining I don’t care much to nitpick around little details. 😛
Precisely!