So i'm in a hotel for a conference in Dubrovnic, Croatia run by the Design society. I encounter this sticker pasted to one of the bathroom mirrors. My initial reaction, 'what cupboard?!'

Well, I'm all for the minimalist, but when it completely ignores functional necessities we run into the unaccetable. Something of the reverse of Gibbson's affordance theory, furthered and developed by Don Norman more specifically within the design context.

Would make a better hiding place than bathroom cabinet. And that's the point. Good design must satisfy functional requirements derived from expectations towards use. In this case, its initial inability to function as required necessitates a sign to uncover the truth. Well, some of my Korean speaking friends would still struggle...

This breaks the 'must have need' described by Kano in his taxonomy of customer needs. A bathroom cupboard must be visible and accessible. Its not enough, in this context, to cry 'for the aesthetic', as evidenced by the requirement to add-in the sticker (no doubt a result of continuous questions to reception/housekeeping on the whereabouts of the room's hairdryer).

Good design always considers form and function.