How do you understand the saying that a married daughter throws away water?

As the times move forward, it is becoming more and more common for young people to go out to study or work. The phenomenon of long-distance love is blooming everywhere. No matter how far away from home it is, it is basically not a big problem. Modern transportation and communication conditions have gradually made long-distance marriages possible. After marriage, girls rarely take care of their parents because of work, housework, and other problems. Parents of single children are really heartbroken. The days of losing the love and protection of your children are very lonely and scary. This is why most parents don't want their daughters to marry too far away.