I agree with this post but can you clarify what you mean by "you would never end up with stale bits of UI"? What do you mean by "stale bits"? An example of the

I agree with this post but can you clarify what you mean by "you would never end up with stale bits of UI"? What do you mean by "stale bits"? An example of the problem would be useful... and also why the "rerender everything" is a solution to such problem. For instance I already see that something like Mobx that has observable state doesn't need to re-render everything and still gives you guarantees about not having stale values (thanks to the way observable works with it).