Why do the roots of lotus fibrous and short?

Lotus is an aquatic plant. It grows in ponds or lakes. It does not need a well-developed root system because there is enough water in its surroundings. It can easily absorb water through its short roots. Well developed root system is required by land plants so that they can absorb water from great depths of soil. Lotus is a monocot plant and short lived. It has fibrous roots to help it to float on water. Fibrous roots help lotus plant to gain buoyancy, and it does not sink. The aquatic environment of lotus significantly contributes to its root development.

Onion, bamboo, grass and banana also have fibrous root system.