My sister-in-law has been on a bit of a FB rampage recently, posting different pictures, quotes, and links a few times every day. A large percentage of them have been about how only mothers know what true selflessness is, and how motherhood itself is the only truly noble path in life.
I'm sure I'm going to offend people here, but this is such BS. First of all, the vast, vast majority of people don't become parents because they're selfless individuals who want to devote themselves to raising new humans properly. They have kids because they want something little to hug and play with, or because of simple biological urges, or because they simply feel like it's just the thing they're supposed to do. A lot of people fall into it by accident. I'm not saying these are bad reasons, but they don't automatically turn you into a saint. Plus, there's the evolutionary imperative. You're doing all this work to raise YOUR kid and pass on your genes.
Secondly, not having kids doesn't mean you are determined to live only for yourself the rest of your life. Maybe you are thinking of how shitty the world is going to be for the next generations. Maybe you recognize parts of yourself that you don't want to pass on. Maybe you do want to devote your life to other people, but those people already exist in the world. Maybe you live in a part of the world where having children means giving up your job and financial security for your family. Maybe you can't have children, and don't want (or can't afford) to spend tens of thousands of dollars to correct the issue. And let's face it. People without kids generally have more time and money to devote to other causes and charities.
Parenthood is hard work. However, sometimes having a kid is the most selfish thing you can do. I'm not saying all parents are bad, or all childless people are paragons of virtue, but I wish we could just stop with the idolizing of motherhood. It's one path of life out of many, and I hate the thought of all my nieces and nephews thinking of it as the best one for women.