Team 4 Principle #4: Performance Load

Performance Load

Performance load is the amount of effort required to complete a task. So, if the performance load is high, the task is more likely to take longer and/or fail than if the performance load were low. This seems like common sense that if something is hard to do, that you might take longer to do it or possibly fail, but often this isn’t considered in design. In my experience at work, I’ve found that having a name to describe this really helps make it a legitimate topic to discuss and explore with research.

There are two types of performance load: cognitive load and kinematic load. Cognitive load is the amount of mental effort it takes. For example, remembering a password to log into a website or application is an example of cognitive load. How many times have you been frustrated by that or just given up? Most of the time my laptop remembers my passwords for me so my cognitive load has been reduced. Kinematic load is the amount of physical effort required to complete a task. For example a manual transmission has a higher kinematic load than an automatic due to the effort required to operate the clutch and the gear shift.

Good design can help decrease performance load and increase the likelihood of people accomplishing their goals. Cognitive load can be reduced by organizing layouts, way-finding, and controls in ways that make sense to people. Chunking can also be used to organize information so users can find it more easily and intuitively. By reducing the physical force and number of steps required to accomplish a task, the kinematic load is lessened and people are more likely to complete the task successfully.

Examples from the readings

Drawings of an electronic car key, casino slots machines, browser bookmarks, and a UPC code. — Examples from our text reductions of performance load. Electronic car keys and electronic slot machines take less effort than manual ones. Computer browsers save bookmarks so users don’t have to remember them or write them down and UPC codes allow cashiers to scan an item versus having to remember and then type in a code.

Examples from the Web

A screenshot of Apple's support website with dozen of pictures of laptops and captions with the year they were manufactured. — On Apple’s website if you want to download the user guide for your laptop, you need to identify the year it was manufactured. This requires cognitive load because the user has to recall the year. If the computer is several years old, this may be difficult. Image source: Apple Support

Examples from the World

A lawnmower with a cord pull to turn it on. — This is our lawnmower. The kinematic load is very high for this machine because a lot of strength is required to pull the cord very quickly to start it.

Works Cited

Lidwell, W., Holden, K., & Butler, J. (2010). Universal principles of design, revised and updated: 125 ways to enhance usability, influence perception, increase appeal, make better design decisions, and teach through design. Rockport Pub. PP. 178-9.

One Reply to “Team 4 Principle #4: Performance Load”

clarah2 says:

October 16, 2018 at 11:19 am

I like the way that you describe the difference between cognitive and kinematic load clearly, and provide ways to reduce the load. It might be easier to digest the information if it was broken up into bullet points, rather than full sentences–less cognitive load 😉

An example of performance load is my work’s website, https://colburnschool.edu. Everyone always complains that things are hard to find on the website, but I think the main problem is that there aren’t drop-down menus. Every menu option has its own landing page, so it takes many clicks to explore the site. It’s really hard to find what you’re looking for if you don’t already know what category it’s in. I reduce kinematic load by using the search bar for almost everything.