Consistency Abused

Amongst the many tools available to designers, design principles are key and fundamental. Teams create custom design principles for a specific project or product, authors sell their own comprehensive list with cool terms or phrases, and some companies have modeled their mottos or mission statements around one or more overarching principles. Of all the known design principles, there is one that has been around for a long time and is used extensively. I’m talking about the principle of consistency. It is probably the most familiar design principle; so much so that you’ll frequently hear non-designers talking about it. As a matter of fact, consistency has become so commonplace that it may no longer be thought of as a principle and viewed instead as a “given” or an ante. Nevertheless, consistency seems to also be the most mis-used design principle.

How can a design principle be mis-used? Wouldn’t the direct application of it ensure goodness and benefits? Unfortunately, no. Generally, principles are intentionally high level in order to be more broadly applicable. This makes them subject to interpretation and hence no real way to “directly apply it”. Furthermore, context will vary wherein goals, priorities, constraints, and a host of other factors and considerations require designers to expertly make tradeoffs. Thus, both context and the expertise of the designer will play a major role in the use of design principles. For example, junior designers look to the more literal interpretations whereas seasoned designers can also look to the spirit of the design principle and thus expand possibilities.

Here are some examples I’ve seen along with proposals:

Physical Consistency

The idea is to put the same UI element consistently in the same ‘physical location’ on-screen.  This is not wrong and in its simplest form works quite well. However, when other factors push against this, blindly sticking with the literal interpretation of physical consistency is too limiting. So, if you want some of the benefits of physical consistency but without being dogmatic about the exact X/Y coordinates, consider semantic consistency.  Place the UI element in the same consistent conceptual location, for example, always first, last, top, or bottom most item. In such cases, users can still predict where to look to find a specific item, but rather than looking at an exact X/Y screen coordinate, they can look in the general area and quickly finding the item based on the rule governing it’s location.

Consistency for the Sake of Consistency

How often have great designs been rejected in favor of staying consistent with an existing solution? Sometimes the existing solution is fine, and sometimes it happens to have known shortcomings. Unfortunately, in either case there’s a reason for not updating or fixing it now and so when it’s time for new additions the question becomes “is it better to be consistent (or consistently bad)?” Well, Of course, there is value in being consistent, however, I prefer a more nuanced version of the principle: “Be consistent in the absence of a better solution.” While this enables continued creativity, the key to properly using it involves determining if your (inconsistent) solution is better than a consistent one. In other words, its value has to be high enough to also overcome any cost associated with being inconsistent. If the value is there, perhaps in time, other parts of the product will be considered “inconsistent” and will be updated to align with your new better solution.

I’ll revisit this post to add more over time; of course, I encourage you to add to the conversation with your own opinion and/or examples.