One of the possibly less known reasons why Google Maps is so accurate and so detailed is that it relies on its users for input. The "edit this map" link is now visible on every map. And the Google Map Maker program is responsible for mapping entire countries, in record time.
This would not be possible without the help of volunteers, but the people that take time to add new locations, correct mistakes or update maps, get little reward besides the knowledge that they have made Maps better and helped potentially millions of people.
But Google now has something much better than the warm feeling of helping others: badges. Badges turn all of this into a competition, and everything is better when you're competing with others.
"You’ve been working hard to build the most comprehensive world map, and now you can share those accomplishments with the new Google Map Maker Badges," Google explained
"You can earn badges for everything from making your first edit in Map Maker, to organizing a MapUp event or contributing to Map Makerpedia," it added.