Wearing anklets is a sign of the marital status in many Hindu cultures and is considered to be a symbol of good luck for herself and her husband.
A scientific reason given for wearing anklets is that by wearing the anklets, one's energy is not wasted but re-vibrated back to one's own body. Also, since the woman wears a lot of gold jewellery in any Hindu religion, a lot of electricals currents are produced in the body. To counter these currents and to keep the positive energy flowing in the body, the practise of wearing Silver anklets is established.
Another reason for women being decked up with ornaments from head to toe was that it is considered a woman's duty to forever be at her best with pleasant appearance in front of her husband and relatives. Hence the elaborate regimen for various ornaments with equal importance given to wearing anklets and toe rings etc.
But the most plausible and relavnt explanation that I was given by someone and the one that I liked was that: from the ancient times, people who were wealthy chose to turn their wealth into precious metal such as gold, silver etc. since there were no banks to keep their money into. Also in those days, a rigid code of conduct was followed where the honour and sanctity of women was concerned. Therefore, most of the wealth amassed was turned into ornaments that could be worn, which when bad times fell could be sold and the family could buy food and necessities with. Later on, this only became a sign of status and symbol in the community and more recently, only a fashion trend.
But mostly, the reason why girls like to wear anklets is that they are simply beautiful and sexy with pleasing tinkling sound.