How are clients impacted by API deprecation policies?
Application Programming Interfaces (APIs) are a tremendous resource—that is, when they are stable. Several studies have shown that this is unfortunately not the case. Of those, a large-scale study of API changes in the Pharo Smalltalk ecosystem documented several findings about API deprecations and their impact on API clients.
More: https://link.springer.com/article/10.1007/s10664-017-9554-9