For using osm as a map, it’s great and very detailed. For cycling navigation it’s ideal. And beats Google maps that fails to find a route without a data connection. Like when roaming. And in many poorer countries, where humanitarian agencies desperately need maps, Google doesn’t bother to map any details, because there is no money in it for them. Fail again.
And, as with railways, companies love to build new, as you get a monopoly. But maintenance? No financial benefit to doing that.