Hello!

I'm pretty sure that "turn right" or "continue straight" when coming up to roundabouts is based off of the angle of the exit that must be taken relative to the angle you are approaching the roundabout at. For example, you are approaching a roundabout and the exit you must take is more or less straight across from the road of approach. Draw a line from the center of the road of approach the whole way across the roundabout to the other side. If the required exit does not deviate more than +/-15° from the line that was just drawn, Waze could say "continue straight at the roundabout" or something along those lines. It could also say "take the second exit at the roundabout" assuming there is one roundabout you would pass on your way to the second exit. I don't really know what conditions must be satisfied for Waze to either say one or the other, but I do wish that it always told you the number of exits to the exit you would take, and not flip flop between the two. It would make things a lot easier and consistent, especially when you sometimes can't tell what "straight" is.

EDIT: Based off the article linked above, I was correct. If the required exit is more than 15 degrees off of an imaginary 0 degrees and 90 degrees line drawn in the roundabout, (a plus) Waze will go by the number of exits instead of a worded instruction like "go straight".

The USA wiki page has info on this:
https://wiki.waze.com/wiki/Roundabouts/ ... structions