Equal power of voting needed?

We are the biggest democracy in the world .What good is it for us? It gives every individual power to choose the leader,whether he is uneducated,illiterate,irrational or closed minded .The voters exercise vote on caste basis,language, ethnicity etc .They elect criminals and demagogues. A citizen of US or Europe knows what's best for him and vote accordingly.But here

the individual himself does not know what his best for him. So should he be allowed to vote.

Should there be equal power of voting with all?Cant we have oligarchy or elitism ?