I think there's a slight difference between bad spelling and grammar errors. As a non-native speaker, I can say the former ones are a lot easier to catch. That's because, for example, if you read a lot you end up "storing" the right way to write a word. That makes you able to spot bad spelling easily. On the contrary, if you didn't get a proper education in english, sometimes you wouldn't be able to grasp the correct grammar structures behind a sentence, thus you miss.

Coming back on topic, I hate when I find mistakes in scanlations, both translation and editing-wise. Whenever I miss a mistake, I hate myself too. I try to improve after each QC, I accept criticisms if they are meant to make me improve. Though in this world, I rarely see the same attitude, people just want downloads and nothing more. It's kind of sad, actually.

I do get really pissed off when there's bad grammar and spelling in scanlations. I'm not talking about the occasional error, because everyone makes mistakes. I'm talking about the people who really don't have a good grasp of the English language. Where almost every sentence in the manga has a mistake. I shouldn't have to re-translate everything in my head to understand what's going on in a series. I feel like these people don't really have a purpose being involved in translating. I also wonder why there isn't someone around to ask to proofread. Even if the person can't do the translating from Japanese to English, why can't you ask someone who knows English well if your scanlation makes sense when you know you are really bad at English?

Most leechers are perfectly fine with mangled English. Also, your idea that it's so easy to get someone to proofread (and do a good job of it) is very naive. Put those two factors together, and you get what you get.

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I have to say that it irritates me very much, but... I can deal with it if I am really wanting to read something. On the other hand if a better group is doing the series I will immediately switch.

I find minor grammar and spelling errors, for instance incorrect word order, tolerable and sometimes amusing. I can chalk it up to being pressed for time and the errors slipped by. What bugs me the most ,and this is strange, is the mixing of Western and British English verbs together in a character's script. For the people that had no idea that there was more than one variety of English look up, learn. More specifically, learnt. The spell-checker here picks learnt up as being misspelled, however, it is actually correct. Learnt is the British English past participle of learn. The Western English version is learned. So, both are correct. However, when I see a mixing I imagine the character suddenly and for no reason slipping into an accent and it completely ruins the scene for me.

"A lot of" feels exaggerated. I agree that it adds some flavor to the text, but I honestly don't think it's as much as many fan translators want to give the impression of.

I'm fine as long as the manga wasn't translated with Google and pasted with out even checking to try and give it coherence.

If i can understand it i don't really care.