I recently noticed that voice messages produced by Google Maps driving directions changed from “turn left onto Foobar street”, and “in 2 miles take exit 27 towards Sleepytown” to simply “turn left” and “in 2 miles take interchange on the right”. This first happened when I was traveling abroad, and I attributed it to the limited information about that particular place (Iceland). However, when I returned home, the reduced messages continued, and this was definitely not normal.
The solution was to go to the settings of my Samsung Galaxy S5, then Accessibility->Vision(!)->Text-to-speech options, and change “Preferred TTS engine” from Samsung to Google.
I am not sure what and when changed this setting, and frankly “Vision” is the last thing that comes to my mind when troubleshooting the speech synthesizer, but all is well that ends well. I switched to Google speech engine and now Google Maps is back to its normal self.