system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does Google Maps sometimes default to a particular route while simultaneously telling you another route is a minute or two faster?
gpt
One thing Google tries to do (and Waze too, for that matter) is stagger drivers across different routes so that one route doesn't get too plugged up. If one route is 2 minutes faster and the routing server gave everybody that route every single time, it wouldn't be the fastest route anymore before too long.

It also gives you that option because you should be able to override the decision that the routing server made for you if you so choose. And most of the time you can with no problems, if you just look at traffic conditions along that route. But that's the ultimate goal, to stagger people across different routes so as to keep the traffic flow more or less balanced (even though it will never be quite so perfect).