If the college has the right to overrule the people, what is the purpose of people voting in the first place
The electors' job is to deliver the results of the presidential ballot counts in each state to Congress and formalize and certify the election at the national level in order to install the president-elect in office at inauguration time.
If there is unrest in some states, or recounts are needed, or certain states are seceding from the union, or some other breakdown in the process occurs, the Electoral College system is designed to ensure resilience, disaster recovery, and continuity of government.
The electors have sworn an oath to faithfully represent the votes of their home states. If they vote otherwise, then they are dealt with after the manner of oath-breakers. Nonetheless, the electors may in certain situations have to make unanticipated and unforeseen human decisions.