Heuristic evaluation is a usability inspection method used to identify usability problems in a user interface (UI) design. It involves a small group of evaluators (usually usability experts) who examine the interface and assess its compliance with recognized usability principles, known as “heuristics.” The goal is to find issues that make the interface difficult or frustrating to use, so that they can be addressed before further development or release.

The method is quick, cost-effective, and highly practical, making it popular in early stages of design and development.

Key Characteristics of Heuristic Evaluation:

1. Small Number of Evaluators: Typically, 3 to 5 evaluators review the interface independently. Each evaluator brings a unique perspective, and by using multiple evaluators, more usability problems can be uncovered.
2. Heuristics Used: The evaluation is based on a set of heuristics, or general principles for usability. The most common set comes from Jakob Nielsen’s 10 Usability Heuristics for User Interface Design:
   • Visibility of system status: The system should keep users informed about what is going on, with timely feedback.
   • Match between system and the real world: The system should speak the users’ language, using familiar concepts.
   • User control and freedom: Users should be able to undo or redo actions easily.
   • Consistency and standards: Interfaces should follow conventions so users don’t have to guess what things mean.
   • Error prevention: Design should prevent errors from happening or provide clear instructions.
   • Recognition rather than recall: Minimize the user’s memory load by making options and actions visible.
   • Flexibility and efficiency of use: Provide shortcuts for expert users.
   • Aesthetic and minimalist design: Do not clutter the interface with irrelevant information.
   • Help users recognize, diagnose, and recover from errors: Error messages should be clear and guide users to resolve issues.
   • Help and documentation: Provide easily accessible and useful help resources.
3. Independent Evaluation: Each evaluator inspects the interface on their own. This reduces bias and increases the likelihood of finding a broader range of issues.
4. Severity Ratings: Evaluators often assign severity ratings to the problems they find. This helps prioritize which issues need to be addressed first, based on their impact on the user experience.

Steps in a Heuristic Evaluation:

1. Planning: Define the goals, scope of the evaluation, and select the evaluators.
2. Briefing: Introduce evaluators to the interface and its intended purpose or user tasks.
3. Evaluation: Evaluators individually review the interface, noting any usability problems they encounter.
4. Debriefing: The evaluators meet to discuss the issues found, and severity ratings may be assigned.
5. Reporting: A final report is produced that outlines the problems, along with recommendations for fixes.

Benefits:

• Cost-effective: Requires fewer resources than formal usability testing.
• Fast: Can be done quickly, especially with a small team.
• Insightful: Provides deep insights into usability problems early in the design process.

Limitations:

• Subjectivity: Depends on the skills and experience of the evaluators.
• Not user-centered: Evaluators aren’t the end users, so some issues may not be uncovered.
• Limited scope: Might miss deeper usability problems that emerge from actual user interaction.

Heuristic evaluation is especially useful in early-stage design but can be complemented by other usability testing methods to capture a more complete view of user experience.