We let people choose the government, but we don't let them make important decisions (except in rare cases when the government is foolish enough to hold a referendum).

The whole point of representative democracy is to put a firewall between the "the masses" and decision-making, while allowing them some influence.

Historically, party and other elites have also largely controlled who was in a position to become a representative in the first place, although that stops working when the elites become completely out-of-touch with the electorate (hence Trump).