It is worth noting that Google themselves didn't offer turn-by-turn directions until Android 2.0 (October 2009). Interestingly, Google Maps Navigation launched

It is worth noting that Google themselves didn't offer turn-by-turn directions until Android 2.0 (October 2009). Interestingly, Google Maps Navigation launched in the US shortly after they had ditched Tele Atlas (owned by TomTom) as a US data provider. It was speculated (though not confirmed, as far as I could find) that Google ended the relationship because it was too expensive/restrictive with respect to turn-by-turn navigation. That makes me wonder if original turn-by-turn restrictions were Google's idea or a requirement of Google's existing contracts. If so, it's obvious Google decided to continue those restrictions for their own reasons and so history has repeated itself.