> They are hugely important for introducing new behavior on existing interfaces without breaking compability. That was bugging me too, thanks for the explanati

> They are hugely important for introducing new behavior on existing interfaces without breaking compability. That was bugging me too, thanks for the explanation. My problem is the same was said for implementing Generics with type erasure. Doesn't make it a good feature for anyone starting a new project. I wish when they soiled the language for compatibility reasons that they would make it an "opt-in" feature. As far as I can tell, interface defaults don't provide much value over compatibility.