As someone who is actually educated, a female and feminist.

Let me go through a little and very generally what terrible writing of a female characters really is.

A thread. I guess.

Many men fail to bring their female characters to life. They often feel one dimensional and completely lack any complexity or depth.

You can tell how a male writer views a woman by how he writes her in relationship with a man. Is she submissive? Does she speak out?

Women who are written to voice their opinions and ambition by terrible male writers make them seem like demons by how they choose to showcase them.

As greedy, power hungry - basically unnatural. Often not feminine enough.

They are presented as vicious and terrible.

Some male writers even go as far as make the female character the reason the male character fails. She is at fault.

This can be seen in very popular literature like Macbeth.

Ever heard of the Bechdel test for media (more specifically film/movies)?

It has 3 basic requirements to pass it.

1. Two named female characters.
2. They have to talk to each other
3. The topic isn't about a man.

Around half the movies fail this test.

There is also the idea of a perfect woman being pretty, submissive, loyal, virgin-like. Basically unreal.

Has no ambitions of her own, is quiet etc.

Even when characters are written with personality. Most of the time they are written to for the male characters. Their whole existence is for them. Which makes them badly written.

They have mostly one side to them and it's related to a male character.

So when do make writers actually write good female characters?

When the female character has her own thoughts, ideas, dreams and personality. She has a complex personality which isn't always "attractive".

She exist outside of the male characters. She is her own person.

A male writer has succeeded in writing diverse female characters when you can describe each and every female character differently. Use a huge diversity of adjectives. They feel like real females in your life. Their personality/reactions are relatable. They are their own person.

Just to repeat myself. This is very basic. Very generally. There can be times the very same writer writes one amazing written female character and while one is very poorly written.

There can be male writers who write amazing female characters but... they are all the same.

This problem is complex and this thread barely covers it.

And before anyone else says it. Yes female writers can write terrible/poorly written female characters as well.

Hope this clears up a little about writing women.