Many organisations do not bother measuring the success of their UX Designs. The aim of your UX is to promote a digital product or service, so it is important to measure the usability of your products and services. In this article we will explore what we can measure and how to use usability metrics to do this.
Usability Framework:
The usability framework uses 3 standards to measure the convenience of a product or service:
- Effectiveness - refers to the precision and extent to which a goal has been achieved.
- Efficiency - concerns the resources employed by the designer to reach their goal.
- Satisfaction - refers to the user’s opinions and experience with the UI.
Without satisfying the above goals, a product will neither achieve its usability goals.
Why should you measure usability?
There are a plethora of reasons to measure usability:
● Reduce the cognitive load of your users
Think from the perspective of your users, not you:
As some one well-versed in the language of computers, what seems simple to you may seem complex to your users. A poor usability will increase the cognitive load of your users, which maystimulate anger and frustration. The last thing you want are these negative emotions to be linked to your brand.
Increase your understanding of product positioning:
To have a competitive advantage over similar products is a must. Usability testing will give you an idea if your product is sitting at a competitive level.
Improve the communication between your focus group and design team:
Usability metrics can help designers understand the areas they need to improve in, and deliberate this with their users/focus groups.
Make effectual decisions:
Your team will be guided on which aspects of the product or service to improve with usability metrics, which are outlined below.
5 Usability Metrics and How ToMeasure Them:
Outlined below are 5 usability metrics which will allow you to measure your achievement of the 3 goals under the usability framework.
1. Task time:
Description: Task time refers to the amount of time a user spends on completing an action. Ideally, the user should be spending as little time as possible on an action - they should have a reduced cognitive load.
Measuring task time: Designers can simulate scenarios for their focus groups to complete, and measure the time taken.Designers should record the:
● Mean time spent on task - the average time users spent completing the task.
● Average time to fail - the average time users spent before completing the task with errors or giving up entirely.
● Mean task completion time - the average time taken by users to complete the task successfully.
Consider: Designers must also consider external factors to ensure users aren’t distracted while completing tasks. Task times are all relative to the user completing them.
Example: Find a particular page on a website.The designer can use a focus group of 15 users and ask them to perform this task. The designer should record the time each user spends on this task, and divide the total by the number of participants. The resultant value is the average time taken to find that particular page. If the average time is more than the expected time, the designer should focus on easing navigation.
2. Errors
Description - Designers will be able to understand how and where users run into problems when attempting to achieve their goals. Errors can reduce usability, thus preventing users from returning to the page. The more errors a user makes, the less usable the software.
Measuring errors: Create a task for your user and measure all the accidental actions, slips and mistakes that they make.
Consider: Categorising errors will allow amore effective combat against every problem.
Example: Consider a situation where users are asked to find a call-to-action and fill this information out. Note all them is takes the user is making. If they are making a large number of mistakes, the designer should work on the usability of this.
3. Satisfaction with task
Description: Task satisfaction refers to how happy a user is with completing a task.
Measuring satisfaction: After a user has finished at ask, ask them questions regarding the task’s difficulty and what they enjoyed.
Consider: Designers simply cannot interview hundreds of users. A solution to this is to gather feedback using the 5 levels of satisfaction:
● Very bad
● Bad
● Neutral
● Good
● Very good
This tactic will give you the priceless, emotional-insights that users have towards your product.
4. Completion rate
Description: Refers to the time taken to complete a task.
Measuring the completion rate: Set your user a task. If they complete it, they pass. If they don’t complete it, they do not pass.
Inspection: Designers simply cannot interview hundreds of users. A solution to this is to gather feedback using the 5 levels of satisfaction:
● Very bad
● Bad
● Neutral
● Good
● Very good
This tactic will give you the priceless, emotional-insights that users have towards your product.
5. Usability problems
Description: This metric of usability focuses on problems that can occur at any time during the user’s interaction with the UI. they include:
● Misinterpretation of content
● Expressing frustration
● Cannot complete a task because of a hindrance from the application.
Measuring usability problems: After setting a task for the user, record every usability problem. After this, interview the users and ask them why they encountered such problems to pinpoint what exactly you need to fix.
Inspection: Note that usability issues are dependent on the type of user using them (for example if the user is family with technology or not).
Comparing two designs
Making users complete tasks for two designs of the same application can assist your usability testing. If your findings show that the rate of completion is faster in one design than the other, this indicates that the user has completed tasks more optimally in that design. Remember that it is difficult to get users toper form tasks in seconds, so invest your time wisely when redesigning your application.
Summarising results:
Every usability test performed should have results summarised. Designers should balance an understanding of performance versus satisfaction of their application.
Conclusion:
Allin all, measuring usability will help designers improve their interface by better understanding their users interactions with their applications.Usability metrics can pinpoint areas of improvement all the while considering a user’s experiences, which is invaluable.
