No, 3 and 9 together mean you cannot ever replace something good with something better.
3 doesn't require that the thing replaced be good. So both 3 and 9 allow you to replace something bad with something good. I only claimed that there are examples where you can satisfy 3 and 9, not that you can always satisfy 3 and 9.
But also, I think this thread entirely misses the point and intended use-case for this list.
When you cannot satisfy all criteria, the list does not become a justification for the status quo. Instead, it is a useful mechanism for elucidating the exact conflicts which a good designer must reason through and ultimately resolve (perhaps even leading to an alternative, "win-win" or "win-less lose" solution. Or not. Either way, the list helped think things through.)
Re:HomeKit
by maxerickson on Monday June 02, 2014 @11:35PM
(#7838002)
3 is talking about technology.
9 is talking about aspects of people's lives.
Something that achieves 3 without sacrificing 9 is probably better (or at least more likely to be adopted) than something that achieves 3 but sacrifices 9.