[abakker]

Definitely true. APIs aren't standard, they aren't guaranteed, and they require constant vigilance from the consuming app's POV. Notably though, these aren't mostly paid APIs. If its free data, then the developers should do what they think best presents the free data they are giving away.

On the other hand, if you want a great example of how to do it right, salesforce.com has a pretty great API strategy. rather than try for some "version-less ideal" API, they release new versions and new endpoints, and have only ever deprecated old APIs for security reasons.

I suspect that when APIs are changing all the time, it is because the API's implementation is too close to the underlying application or data structure. In an ideal state, the APIs are only supposed to present data in a certain way, and shouldn't necessarily be determined by the actual structure of that data in an application or database.