Its called constructive criticism. Telling people only that they did wrong, and that they are bad, is a good way to kill self-esteem especially for people who are new. Insulting them and saying, oh well I could have done it better, actually does make you look like a douche, and in the end only hurts the people who you are insulting, along side yourself.
But on the other hand, its true that without some kind of guidance, people may never learn from their mistakes. But it helps if you dont try and make it sound as if you could have done it better, even though you might have been able to. Being friendly when criticizing people also really helps to, as they will take it as you trying to help them, instead of you trying to hog some kind of spotlight. (some people just QQ about all criticism, but those people dont really deserve any in the first place then)
I am however going to avoid a poll for this, because I have no idea who the fuck you are. Meaning I dont know how it is you criticize people, or if people agree with what you say. And also, I really try to stay out of these popularity contests of testosterone pumped kids on the internet. But thats my 2 cents anyways.