The mother knew (from experience?) that she did not have the necessary impulse-control, or intrinsic motivation, to save money for such a long-term thing as a dowry.

I was really taken by this example because my initial reaction was "just try harder". My first-world perspective has always been "if you failed, its a personal short-coming. You need to become better".

This mother's solution is based off a fundamentally different philosophy; "I am not capable of that kind of self-control. I'll modify the environment".