An excess of choices can lead to fatigue and can make people feel dissatisfied with the experience, or even worse, abandon the process altogether. Not only do we feel mentally exhausted when we have to compare too many options, but also, once we’ve decided, we are often left over with a nagging feeling that they missed something important.

Adding marginally useful features to a product can result in overly complicated rather than desirable interfaces. The paradox is that consumers are attracted to a large number of choices and may consider a product more appealing if it has many capabilities, but when it comes to making decisions and actually using the product, having fewer options makes it easier for people to make a selection.

Feature Creep in Action

I recently observed this phenomenon at several restaurants that have sophisticated soda-dispensing machines. These soda fountains give customers the ability to choose and mix over 100 drink flavors using a touchscreen and button interface. The idea might sound cool, but the reality is not so impressive.

Filling up a cup with soda is an activity that usually takes less than 10 seconds. With these fancy machines, some people need more than a minute to complete this simple task. New customers struggle to figure out an unfamiliar touch interface consisting of multiple menu levels. And some end up taking an excessive amount of time experimenting with flavors: they decide on a flavor, navigate to it, dispense the chosen mix, take a sip, pour out, and try again. All this extra work and decision-making results in long lines and grumpy customers.

At a salad bar restaurant: A family struggles to figure out how to use a soda dispenser machine as the line continues to grow with impatient customers.
At a pizza restaurant: How many people does it take fill up a cup with soda? This is a sign of design fail.

Other people who have encountered this machine have expressed similar experiences:

“This machine is a momentum killer, only serves one person at a time including ice. The buttons are vague. I observed one machine in use at a very busy 7-11 last summer and the line was out the door waiting for one person at a time [to] navigate this frustrating machine. Customers were giving up and leaving…Too much tech for a simple need.” – Mike Rogers, http://www.innovationexcellence.com/blog/

“I've found that the machines have a few natural enemies...mainly families with children and the elderly. Both [of] which immediately drag the whole drink process to a halt while a line builds up behind them.” – Kwinke, http://drinks.seriouseats.com/

“I just want a soda, I don't want to program the damn soda fountain. I am a programmer by trade, and want to get away from the office at lunch. I just want a soda, that's it, not a job, and personally, these machines are too much work.” – Kfries, http://www.fool.com/investing/

This soda dispenser might work in other situations, but not in a restaurant full of thirsty, hungry customers. Subjecting the majority of customers to unnecessary complexity just to satisfy a few curious customers is cruel and bad for business.

Tradeoff Between Features and Simplicity

There is tremendous business pressure to tack on options and features to products as a way to differentiate from the competitors or to remain relevant. In designing any user interface, key decisions must be made concerning the tradeoff between feature richness and simplicity. Deciding the acceptable level of functionality is key in creating useful, long-lasting products.

The correct level of choices or features relies on many of factors, including context, the user’s level of commitment and expertise, user goals, and mental capabilities. A factor that remains constant is human mental capacities. Understanding the psychology behind decision making can help you make the right choices for your customers and business.

Simplicity Usually Wins

Humans have limited capacities for processing information and often choose the path of least effort, even though an alternative path would result in better outcomes. Users often take shortcuts and may appear lazy, but their actions are ways of protecting themselves from information overload and fatigue.

All decisions people make require mental effort. As technological advancements proliferate, so does the amount of work required to make good choices. Every decision, large or small, costs us time and effort.

The more features added, the more complicated the interface:

  • More things for users to consider. Each takes time.
  • More explanations, help text, and other instructional overhead as all the features need some kind of exposition.
  • More risk of picking the wrong option or making other errors

Combining different feature interactions causes even more complexity and difficulty for users to form a mental model of what’s happening with the system.

Displaying a high number of options makes the screen appear more crowded and the menus more complex. As a result, it’s harder to notice and attend to the option of interest and users are more likely to make an error and select the wrong choice, either due to a misunderstanding or simple accident.

You may want your customers to explore the interface and discover the plethora of features, but if doing so adds work to an already satisfactory solution, you will encounter great resistance. In the soda machine example, time on task bloated by over 500%. On the web such an increase in time feels like eternity.

People in restaurants might put up with this lack of efficiency because they’ve already paid and are therefore committed. However, web users are usually less committed and have an easy way out: they can simply go somewhere else to find what they need. Ignoring how humans function is a serious mistake that can cost you customers and sales.

Summary

Adding features that have little to no value to most users undermines people’s innate abilities to collect and process information efficiently. Keeping the number of options at a reasonable level allows people to make decisions more easily and complete tasks faster.

Courses on how to apply psychological principles to designs: