Help users do things

Protecting cognitive resources

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Users don’t care how hard you’ve worked to build your product. Or how keen you are for them to love it. What they care about is if the product helps them achieve things and makes them feel good. Our challenge as product developers is to make this happen. A key aspect of designing the user experience is optimising your user’s cognitive resources (short term mental capacity, including willpower).

Today’s post considers the importance of cognitive resource management. This draws upon the insights from Kathy Sierra’s book Badass: Making Users Awesome.

Cognitive resources

None of us are immune to the draining feeling when the product or service we are trying to use just won’t work. We face problem after problem. Our energy and trust wains. Eventually, we give up, exhausted and frustrated. This illustrates the concept of having finite cognitive resources and the need to manage them well.

We can visualise cognitive resources as a finite amount of water in a bath. When users interact with a product an amount of water drains out of the plug hole, to get things done and build expertise. As product developers, we want users to use bath water in an efficient way. Leaks occur when users think about the wrong things, due to a poorly designed user experience.

Micro-leak exhaustion

Psychologists believe that the brain keeps a background process running for unfinished and interrupted tasks. Our brains keep track of these unresolved cognitive tasks long after we have consciously stopped thinking about them. That slow background leak is known as the Zeigarnik Effect. Novelists depend on the cognitive tension caused by unresolved plot elements to keep readers turning the page.

In the context of an app, a common cognitive micro-leak comes from a subtle feeling of uncertainty about whether a small action taken by the user did exactly what was intended. “My photos backed up did complete, didn’t it. I’m 98% sure.” “I did set my phone to silent, didn’t I. I’m 98% sure.” Many tiny leaks can grow into a large puddle of wasted cognitive resources, leaving us feeling exhausted.

Our brain does not need to spend resources worrying about an unfinished cognitive task if it believes something or someone has a trustworthy plan for handling it, e.g. we set an alarm at 7am to wake us up. Even though the task is unfinished (waking up on time), knowing that the job has been delegated to a trusted agent is enough for the brain to act as though it’s already completed.

Extra features

Every new feature added to a system takes users cognitive effort to understand and use. Hence, app developers should consider whether the potential feature contributes sufficiently to the user experience. Perhaps the feature should be hidden or minimised until the user needs to use it - this is progressive disclosure.

Don’t force users to memorise

Delegate cognitive work to something in the user environment so it does not sit in the user’s head and cause leaks. Devices and apps achieve this through well labelled and intuitive controls and interfaces. If a user manual is necessary then you need to redesign your product to make it more intuitive.

Knowledge in head v. world

Learning and memorising consume cognitive resources. However, once through this, using this new knowledge can be fast and efficient. Hence, there is a short term cost versus longer term benefit balance to be assessed. Apps should make it clear to users which processes and facts are worth learning and when to do so.

Affordances

Make the right thing easy and the wrong thing difficult. The more obvious and natural it is for a user to take the right action, the fewer cognitive resources are consumed. Product designers refer to this as Perceived Affordances. If a door handle looks like it should be pulled, rather than pushed, then that’s what people will tend to do.

A natural, obvious, self-evident action can be a perceived affordance, an instinctive reaction, or simply the easiest path of least resistance. - Kathy Sierra

Don’t make users choose

Choices are cognitively expensive both while the choice is being made and afterwards. Leaving a decision to someone else saves cognitive resource in the moment and frees users from the nagging feeling that they made the wrong decision. Choices do give users more control, but at a cost. The product should provide intelligent default options and recommendations. This is particularly important when the user first encounters a product.

Other resources

Don’t Make Me Think book by Steve Krug

Simple and Usable book by Giles Colborne

The Design of Everyday Things book by Donald Norman

This post considered how product designers can help users do things by managing their cognitive resources. Next Sunday’s post will look at how to differentiate a product by choosing suitable competitive axes.

Until next Sunday, think about how your favourite products make you feel and why.

Have fun.

Phil…