Though I'm not a direct user, I've recently seen Waze has some glaring errors that Google Maps doesn't - especially on "special" days.
I saw the most spectacular failure like this on Good Friday this year, where I had to take a cross-town trip and Waze was telling my Bolt driver that it would take 2h+ (and trying to make them avoid all large roads), when in reality and in Google Maps, the city was essentially empty and the trip took ~30 minutes.
The 2h+ estimate was definitely correct for a normal day, but that day was part of a long weekend and no one was around, and yet Waze had absolutely no idea. Even on normal days, it typically significantly overestimates how long rush hour lasts by at least another hour.
Maybe this is somehow specific to my city, but at least it shows that in some places Google Maps and Waze use significantly different data (or weigh different sources very differently).
