"We found that using landmarks in directions helps for two simple reasons: they are easier to see than street signs and they are easier to remember than street names. Spotting a pink building on a corner or remembering to turn after a gas station is much easier than trying to recall an unfamiliar street name."

The Third and Most important reason would be that most of the time, you won't find a board with a road name :). I don't mean it in a bad way, and it has never stopped me from going where I want in india.

The best way to find a route in india (and i guess in most of the fdeveloping countries) is to just stop and ask. and if you are in luck, people will even travel with you to show you the place.

But wonderful thinking from google. they clearly know what they are doing.