I think the answer is simpler than that. The reason that you can't define static methods in an interface is that the Java language specification doesn't allow it. There really is no other reason. When designing a language choices must be made about what is allowed and what isn't, and the designers of Java chose against this one. They could have chosen in favor and there would be very credible arguments for that position.
Some problems are so complex that you have to be highly intelligent and well informed just to be undecided about them. - Laurence J. Peter
Joined: Jan 17, 2006
I just noticed that the answer I gave was almost exactly the one given by EFH in the referenced thread. He says it better than I do so I'll defer to his answer.