[wpietri]

Modal dialogs were always terrible. They were just easy to code, and fit the common programmer mental model of code first, not user first. The NeXT folks clearly recognized that background activity was a concern given how they were using the dock to give app-specific notification. But design-wise it was a cul de sac because it required permanent screen real estate for anything that might matter.

I also don't think multiple discovery is much of a counter to "most things are obvious in retrospect". Yes, design problems can get solved in similar ways by different people. But obvious-in-retrospect thinking is a cognitive error, where we presume that what's obvious to us is obvious to people in different times and conditions.