The root cause for such politcal system in india is the Congress party which has devised plans such as minority appeasement programs to create permanent vote bank started during Nehru's period. Once such policies where in place it was very difficult for other parties to fairly contest elections as win ad congress has the minority vote bank. Soon the other parties started creating similar vote banks by playing caste card and religion card. If any party takes the side of majority community then it is branded as communal party. Even in the History books our the congress party did not allow history text to include the facts like how muslims invaders have destroyed several Hindus temples and several places hindus were killed and raped. But they just blamed britishers.
