You've already got a lot of good answers here - and most share a theme:
There are also other "skills" that go into motherhood like:
Being an efficient manager of the home - you can be the most loving person in the world, but if you can't get to the grocery store regularly, or teach kids to pick up after themselves, they still won't be the happiest kids on the block.
The ability to look at your child objectively - this is not easy for any parent, but it's necessary. A child wants you to see him/her as a whole person, for who they are, not just as "their child." It's important to kids that mom's UNDERSTAND who the child is as a person and demonstrate that understanding by providing the little things, experiences, opportunities that the child will enjoy and later cherish.
I have more, but my child is asking me to play "chase the bears" with her, so guess what. I must stop and give her the ATTENTION she deserves.
Good luck on your paper.