Buses almost always run at less than 50% capacity, as people are going to or from school or work, but not both (i.e. morning rush is in the opposite direction of evening rush). The other unsolvable problems for buses is that they necessarily increase commute distance and time, as people must take a more indirect route to use buses (as opposed to individual transportation), and they are not flexible (i.e. they have limited peak capacity and fixed schedules).