[klodolph]

Question: Doesn't the same thing apply to managed services?

Let's say you want to make a change to the filesystem. You can change the client libraries today, but old client libraries are going to be in production for weeks, or longer. Your filesystem service has to be backwards compatible with some weeks or months of filesystem libraries.

[inoffensivename]

Yes, and this is a good thing! If you're building infrastructure that people are going to come to rely on, it shouldn't change very much. Its interface certainly shouldn't change without very good reason.

Another problem Google has is that people feel the need to change things in order to get promoted.