These are design factors related to cognition and thought processes. Detailed consideration of these factors is necessary, since users are affected by their surroundings.

Unable to Concentrate

Repetition of monotonous tasks reduces the ability to concentrate. And when users are in a rush, they may make mistakes with even simple operations. Therefore, products must be designed so users can recover from incorrect or accidental operations.

Unable to Recognize Mistakes

No user can immediately understand unfamiliar technical terms. Users are also confused by controls that work in a different way than what they are used to. Therefore, readily understood terminology and standardized usage methods are important.

Unable to Get Expected Results

Controls that require special actions, complex and detailed operations, or complicated procedures take time and effort to perform even if well understood. Therefore, products need to have as simple controls as possible.

Unable to Remember How to Use a Product

Products must be designed to eliminate the stress of not being able to remember an operation used previously or being confused by lots of unfamiliar terms.

Figuring Out How a Product Works Takes Too Long

Overly complex systems and mechanisms can be nearly impossible to understand. And users find it difficult to remember information that seems unrelated to them. Therefore, products need to be designed so their operations are easily understood as well as so they can be used without understanding how they work.

Unable to Identify Controls

It is extremely hard for users to tell unfamiliar graphic symbols apart. Therefore, it is necessary to use familiar graphic symbols and terms whenever possible.

Unable to Understand Causes and Effects

Users get stressed when they cannot figure out how something happened. Therefore, designs must incorporate straightforward ways of showing or communicating how to avoid problems as well as understanding causes and effects.

Environmental Distractions

Products must be designed so operations can be quickly remembered and resumed when users are interrupted by something around them, such as someone talking to them.

Miss Situational Information

If operations take place over a large area, users can easily miss important situational information. Therefore, products must be designed with various notification means, such as sounds and lights.