Understanding Usability
Usability
The degree to which a product enables specified users to achieve defined goals effectively, efficiently, and with consistency and predictability.
Usability is not just about functionality, it's about creating a seamless and enjoyable user experience.
The Five Usability Objectives
Usability objectives
Usability objectives include learnability, efficiency, memorability, errors and
satisfaction. These objectives provide a framework for evaluating and improving products.
- Learnability
- Efficiency
- Memorability
- Errors
- Satisfaction
1 - Learnability
Learnability (usability)
The ease with which a user can reach a defined level of competence with a product or system after a set amount of training or use.
- Intuitive Design: Are the controls and features easy to understand without a manual?
- Clear Instructions: Are there helpful guides or tutorials for new users?
- Consistent Interface: Does the design follow familiar patterns and conventions?
- Consider a new smartphone app.
- If users can navigate its features without extensive instructions, it has high learnability.
2 - Efficiency
Efficiency (usability)
A usability objective that measures the speed and accuracy with which users can perform the intended task of a product.
- Streamlined Processes: Are there shortcuts or automation to speed up tasks?
- Minimal Steps: Can users achieve their goals with minimal effort?
- Responsive Design: Does the product respond quickly to user inputs?
3 - Memorability
Memorability (usability)
A usability objective that measures how well a user can recall how to use a product after a period of not using it.
- Consistent Navigation: Are menus and features logically organized?
- Familiar Icons: Do icons and symbols align with user expectations?
- Reinforcement: Are there reminders or prompts to help users recall functions?
- Think of memorability like riding a bicycle.
- Once you've learned, you can easily pick it up again, even after a long break.
4 - Errors
Errors (usability)
A usability objective that measures the number, frequency, and severity of mistakes users make when using a product.
- Error Prevention: Are there safeguards to prevent common mistakes?
- Clear Feedback: Do error messages clearly explain what went wrong and how to fix it?
- Easy Recovery: Can users easily undo actions or correct errors?
A word processor with an "undo" feature and clear error messages helps users recover from mistakes, enhancing usability.
5 - Satisfaction
Satisfaction (usability)
A usability objective that reflects how pleasant a product is to use, based on how well it meets the user’s needs, expectations, and preferences.
- Aesthetic Design: Is the product visually appealing?
- Emotional Engagement: Does the product evoke positive emotions?
- User Feedback: Do users report high levels of satisfaction in surveys or reviews?
- Satisfaction is subjective and can vary widely among users.
- It's important to gather diverse feedback to get a complete picture.
Reflection and Application
- Evaluate a product you use regularly. How does it perform against the five usability objectives?
- Consider a product that you found difficult to use. Which usability objectives were not met, and how could they be improved?
How do emotions and personal preference influence our perception of usability?
