are people who only tell you that you suck, you ain't as good as them, you will not make it, you can't be understood, you make it look weird, nobody wants to read what you wrote, they just correct you and let it look like as if your imperfections would be the worst without talking to you about how to improve yourself.
Not everyone is perfect, most are not even perfect in their mother tongue, so it sucks if you try to do the best you can but all you get back is negativity from some strangers who don't even know you.