Because nobody knows what the street names are. Or which direction (E-W/N-S) they run. Everybody goes by these really absurd landmark-based instructions like "Turn left at the second signal after the big lotus shaped petrol* station". Sometimes the directions require prior knowledge: "Do you know where Lilavati Hospital is? Right. There's a church adjacent to it, across from which is a lane, with a bank on the left. Across the street from the bank is the building you want".
We're doomed. No matter how much research you put into it, I just don't think directions like "Make a u-turn after you pass the wall with the paan* stain that looks like the Virgin Mary" is something an algorithm can spit out.
*For my American readers^H: petrol=gasoline; paan=chewing tobacco;
Tags: rant, google, maps