A fifth advantage of static factories is that the class of the returned object need not exist when the class containing the method is written. Such flexible static factory methods form the basis of service provider frameworks
I wish he'd not imply coupling between the service provider pattern and static factories pattern. The service provider pattern is often accomplished without static factories, and I might encourage preferring the non-static route first.
edit: <spoiler alert> he touches on this in Item 5. But I think it's worth mentioning explictily here, too.
