When you’ve been doing interaction design for 2 decades you become familiar with the most common gaping holes in the knowledge of the interaction design practice. If I could wave a solstice holiday wand this year, I’d implant the following ideas into people’s heads so we could plug those holes and move the practice forward.
1. Yes, Virginia, it can be defined
If I had a dime for every time I heard “interaction design can’t be defined, but…” I would have…a frustrating amount of dimes. Such proclamations strike me as lazy. Just because it’s difficult doesn’t mean it’s impossible. Let’s give it a shot here.
Design is the optimization of a system for a set of effects.
Bam. Whoa. Simple and powerful, and sets out the hard truths that we are system thinkers with goals.
Interaction (Computer) is the manipulation of state-based systems for a set of implicit goals.
You can imagine different subtleties for interaction (human) and interaction (artificial intelligence) but the above definition works in terms of the way most practitioners practice today. This is the root of our concern for affordances, controls, feedback, mappings, and flow. Together, these make a useful and rich definition of interaction design.
Interaction design is the optimization of state-based systems towards a set of stakeholder effects that include implicit user goals.
No, this is not going to be sung to a crowd of teary-eyed thousands in a stadium with flags bravely waving, but it works.
4. Personas and scenarios are still the best tools
No, personas and scenarios aren’t perfect tools. I’d challenge you to find a perfect tool that works with such complex and often wicked problems. But they’re still the best tools we’ve got.
People are good at people. That’s personas. People are good at stories. That’s scenarios. Conversely, people are generally bad at thinking about users and technology. Personas and scenarios scale. You can use them in a napkin sketch and they can be the basis for a longer-term strategic design initiative.
Lower the cognitive friction of the tools of understanding, and you get to good design quicker and more predictably. If they get you into the right frame of mind for designing and even evaluating design all the better.
No, personas are not perfect. Too many people have seen bad examples of them. Personas can introduce a WYSIATI bias (that is, if you don’t bother to think systemically, see #5, below.) Personas do not address tragedies of the commons. They only account for one part of the triple bottom line evaluations of design strategies. Though they can be fundamental to business goals, it takes several steps of explanation to connect business goals to personas which can look like the results of a creative writing workshop.
Scenarios are not perfect. They can also introduce a WYSIATI bias. Designers can use the instance to hide flaws in the strategy. They can allow a designer to paint the target around the arrow, and have their design work perfect! Every time! They take a lot of caretaking and iteration over the course of a project.
That said, the alternatives to personas and scenarios suck. Designing without them, there is very little way to contextualize design decisions, to prioritize them, to manage trade-offs or to convey why a given design will be effective without them. You’ll end up designing for yourself, or the loudest opinion in the room, or for an “elastic user,” ultimately producing design that fails to inspire love in your product.