Why do women settle for less than the best?

I find it hard to understand why women knowing put their heart and soul into a man who doesnt do the same for them in return. Settling for what right now and what familiar does not equal happiness. He's good in bed or he had a good job is not going to develop a healthy, happy relationship. Women need to step back, look at themselves and find out what it really is they want. But not settle for anything less than that. Work hard to get what it is you want and also make sure you are being the best woman you can be so that when that good man comes your way, you'll know how to keep him.
Thats jus my thoughts- Esha