Sometimes waze will direct me to take a zig zag pattern through downtown Toronto during rush hour, rather than a simple drive along one street, one turn, then up another to reach the same point. Even if those individual segments are statistically faster, the time required to make those repeated left and right hand turns in the height of rush hour is excessive. Frequently only or two cars will get through on each change of the light, pedestrians are often blocking the way (for both right and left hand turns), etc.
Similarly, waze will sometimes direct me take a minor street and then do a left-hand turn across a wide busy street, avoiding a traffic light at a more major intersection that would make the turn easier and more predictable.
Is waze taking the "cost" of these various turns into consideration, or does it primarily (or perhaps only) consider the speed of each segment?