Consistency and the UI of street signs
Excellent concise post by the mighty Wodke on the 'red herring' of consistency in user experience design - not that consistency isn't important in components of the interface (the interaction design), but that it's overplayed in the visual layer/graphic design.
"This is an observation gleaned from web tests ... in the many user research studies I've seen, while users get a lift in ease-of-use, happiness, confidence, etc. from UI object consistency, they are almost utterly unaffected by design consistency. In fact if one is trying to use inconsistency to message a change (of location or of state for example) one has to nearly hit the user over the head with it, using vibrant colors and huge font messaging."
Being of a mind to find analogies in 'real world' design, especially around buildings and architecture, I need look no further than the end of my street. Every morning I step out on to Gower Street and see these four streets facing me at the crossroads of Gower Street with Keppel Street and Store Street. The design of each is different (three subtly, one significantly), and yet it's quite clear a) what they are, and b) what they do. Even the gold coated, raised-letter, deco-styling affixed to the London School of Hygiene and Tropical Medicine is functional whilst being evocative of the building and the area. This inconsistency of design is allowed as basic elements of the user interface of signage remain: a standard way of denoting the street in terms of language construction; a roughly consistent placing on the buildings - above first floor window, below second floor, close to the leading edge of the building (akin to the emerging standard placement of elements of interface design perhaps.) We take these things for granted but context defines the way the signs work, allowing for distinct variation in style whilst remaining usable.
Equally, overconsistency can actually be confusing. Differentiation is important - depending on context. In Clerkenwell, there's a reworked series of shop units down a side street, with a shiny new facia installed by the developers. The sign spans three adjacent units, with exactly the same typeface (face, size, style) denoting each unit, right next to each other, such that it reads 'DENTIST FOOTWEAR PIZZA'. Now, this could be a niche service I'm yet to experience, somehow involving having your teeth checked whilst being sized for shoes made out of pizza ... but I doubt it. All these units are members of the class 'service industries outlets', but in this case differentiation between these units would be more beneficial than this unecessary consistency.
I took signs as an example because I often fall into the trap of using street signs or motorway signs as a 'classic' example when preaching consistency to other designers (i.e. "when you go to an unfamiliar town, you don't have to relearn the way the signage works - why do we have to do that from one bit of a website to another?"). Indeed they are good analogies - when done well, such as those by Margaret Calvert and Jock Kinneir - but I should interrogate that thinking as to exactly why and what consistency and differentiation is important in UI design
