Children hate parents?

Why there are too many children hate their parents?

I know parents always love their children, but not many children in this world love their parents
There are many children said "I hate my parents" and mocking their parents
I know about that feeling

But, everything your parents do that is for their children. They love their children so much.
Many children just look from their side and take their own conclusions
Did they ever look from their parents side?
May be, their parents do something wrong. BUT, children can tell their opinion about that to their parents.
How can the children or parents know about their mistake if there is no one has ever told that?

For the children:
You are alive because and for they are

For the parents:
You are alive for make your children feel a hap