It's happening that you run out of gas and you miss the gas exit.
You want to stop by the rest erea and you miss the resting erea exit.
You want to stop to text and you miss the texting erea.
A lot of the times when you see the exit sing it's to late to stop.
Waze should have the option for a pop up notification a mile or 2 before.
Also a lot of the times you have to get off the highway to fined the gas station so you should be able to click on exit and it should add this stop to your rout