Traffic Lights

Q.  I frequently find myself stopping at a red light, starting up at a green light, driving at the speed limit until the next intersection, and thenstopping at a red light again ------ a continuing pattern.   With the need for fuel efficiency and the availability of technology, why don't cities time traffic lights better, at least on major streets?

A.  Improving traffic lights is an expensive project.  Consider the complications : 
      They change hour by hour throughout the day;  they're different on weekends;  and driving behavior is affected by weather.  Even seasonal variations, such as whether school is in session, have an impact.  And other conditions (construction, sanitation routines, road repairs, etc.) are constantly in flux.
     That said, upgrading our system of traffic lights definitely can be done;  the benefits would be huge, and some immediate.  Imagine:  reducing congestion, saving money on gas, lowering air pollution, and, best of all, decreasing the rate of accidents at intersections.
    Then why isn't it done more often?  In a word, apathy.  Voters aren't exactly energized by traffic lights!