Why do readers hate Mary Sue characters?

Ehhh Mage Sue... Dang it :/ I was working up ideas for my MC who has magic, trying to think of something cool, and I think she's getting a little close to the all-powerful the One who learns in one day what all the other Masters took seven years to learn. : I'd say Mage Sue is the one I see the most often... as long as they're not TOO powerful I think they're alright, but the Misfit Sue can be kind of annoying. But sometimes the Misfit Sue was "beautiful all along" but either had terrible self-confidence (which is saved by the charming boyfriend) or was put down by other girls who were extremely jealous of her.

Or she just needed a haircut >. BQ - I think I see Punk Sue the least, though it may be because I tend to lean toward medieval-ish fantasy (as in with swords, horses, and the rest). Misfit isn't the most common either, but Misfit's very annoying.

BQ 2 - Hmm maybe... it depends how much you restrict your characters, when there's a super powerful Mage Sue it calls for disbelief, but when it's tuned down somewhat it's alright if the rest of the story is good.

Victim! Sue is the most annoying. I mean, get out there and do something, woman!

BQ: Misfit! Sue is probably the least cliche, but I'd rather read about Warrior!Sue. BQ2: Agreed.

A lot of people here seem to worry about whether or not their character is a Mary Sue or Gary Stu and list everything about the character like their talent, hair colour, eye colour, etc. Well, that doesn't make a character a Sue/Stu, it's their actions and stuff that happens to them. So take a chance and write!

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.