Because people voting them are 3rd rate illiterates who have no idea about national issues like how Singapore became advanced, how China followed Singapore model, and became super advanced too. What does the rule of the law even mean? What is equality and fairness? How independent and fair institutions like Judiciary and Police function in advanced nations. How to lay the education foundation so that every person gets highest quality education. How to plan a perfect town or city. How to crackdown on illegal migration, corruption, crime, drugs, Gutka, illegal encroachment, stray dogs etc. How to curb the population growth. How the mixed style economics function. How FDI, FII and geopolitics work.
So, they rather look at the face of the candidate (celebrities like Amitabh Bachchan, Hema Malini, Sunny Deol, Govinda)
OR
they look at his caste or religion. Just blindly someone of their own caste and Muslim Vs Hindu.
OR
They look at his Robinhood persona and trust he will rob the rich and bring social justice and freebies to them and they overlook the credentials of the candidate (Lalu Prasad, Mulayam Singh Yadav, Raja Bhaiyya, DP Yadav and Mayawati) are prime examples.
OR
The worst thing. A wave of sympathy. Like a foolish herd they go out and vote in sympathy. Rajiv Gandhi’s career was over by the late 80s, and he suddenly went into oblivion after he was maligned in Bofors Gun controversy. People were so awash with the new fool at the helm that they didn’t even care whether Rajiv Gandhi was even alive. But when suddenly Rajiv Gandhi was assassinated, in 1991 the whole nation was shocked and same people started crying and came out in huge numbers and voted for his party, and finally his trusted confidant PV Narasimha Rao became the next PM. His incompetent wife became the default KINGMAKER of the country for like good 15-20 years or so. 1991 to 1995, 2003 to 2014.
Another example of sympathy wave when the movie Bandit Queen came out in 1994. It became a cult hit and won critical acclaim internationally. Phoolan Devi, the bandit won the election twice once in 1996 and then in 1999.
Bandit Queen was a Bollywood movie made on real life Bandit, Phoolan Devi, who massacred a whole Thakur village Behmai for her past vendetta against higher caste thakurs who raped her and then she surrendered in 1983. Finally, she was released and joined politics and won the election became an MP (the top parliament post) and got a bungalow in Lutyens Delhi where the who is who of politics live. The political nerve center. On July 25, 2001, Phoolan Devi was assassinated outside her Delhi home. Her killer, Sher Singh Rana, was an upper-caste man who claimed his motive was revenge for the Behmai massacre of 22 upper caste Thakur Rajput.