The Difference Between Completion Rate and Success Rate in UX

Completion and Success Rate are two important metrics used to measure user behavior. While these terms might sound similar, and many designers pursue them as the measurement of practically the same type of success, they capture very different aspects of the user journey.

✅ Completion Rate

Completion Rate measures the percentage of users who successfully complete a task in a flow or process. This metric is often tied to quantitative analytics and is typically used to evaluate broader funnels — such as e-commerce checkouts, form submissions, or any multi-step user interaction.

Example illustrated by NN Group

Imagine that 1,000 users start a multi-step checkout process on an e-commerce site, but only 300 of those users finalize the purchase by reaching the confirmation page. In this case, the completion rate would be 30% (300 completed tasks out of 1,000 initiated tasks).

Completion Rate helps identify drop-off points and friction in the flow, providing insights on where users get stuck or abandon the process altogether. It is essential for spotting bottlenecks and improving the flow’s usability. However, it doesn’t always capture whether users felt successful in completing their overall goal.

✅ Success Rate

Success Rate, on the other hand, measures the percentage of users who achieve their intended goal. This is more qualitative in nature and is typically gauged through usability testing rather than pure analytics. Success Rate emphasizes user intention and goal completion, often associated with how well the design supports the user’s underlying needs.

Example

Let’s assume 40 users are tasked with finding a specific article on a content website. If 36 users manage to find the article (whether via search or navigation), the success rate would be 90%.

Success Rate doesn’t necessarily require users to follow a prescribed path. A user might bypass steps or take an alternative route, but as long as they achieve their goal, it counts toward a positive Success Rate.

Key Differences

Measurement Focus:

• Completion Rate focuses on users following a predefined path, measuring how many users complete all steps.
• Success Rate focuses on whether users achieve their goals, even if they deviate from the prescribed flow.

Evaluation Method:

• Completion Rate is generally measured through analytics tools like Google Analytics or Hotjar, which track page views, clicks, and user progression.
• Success Rate is usually measured through usability testing, which uses direct observation and qualitative feedback to assess whether users reach their desired outcomes.

Use Cases:

• Completion Rate is excellent for evaluating linear, multi-step processes (e.g., checkout funnels, form submissions).
• Success Rate is ideal for evaluating tasks with multiple paths or more exploratory user journeys (e.g., finding information on a site or searching for a product).

🟢 Example of Completion and Success Rates in Scompler

Let’s take a look at how these two metrics would apply to the Scompler content strategy platform, a complex tool for managing content strategies, workflows, and multi-channel publishing.

↘️ Completion Rate in Scompler’s Publishing Workflow

In Scompler, users often need to complete multiple steps to publish content across multiple platforms. Here, the Completion Rate would measure how many users complete the entire publishing workflow, from content creation to publication.

Scenario

Scompler’s publishing workflow includes steps like creating content, tagging collaborators, scheduling posts, and finally publishing the content across various channels.

Completion Rate

Suppose 500 users begin the publishing process by creating a piece of content, but only 200 of them finish all the steps and successfully publish it. This would result in a Completion Rate of 40%. If the drop-off rate between the content creation stage and the scheduling stage is high, this indicates friction, and designers need to investigate why users aren’t proceeding to the next step.

In this context, improving the Completion Rate might involve simplifying the scheduling interface or providing clearer instructions on finalizing posts, ensuring users progress smoothly from one step to the next.

↘️ Success Rate in Scompler’s Search Functionality

Now consider the Success Rate for users looking for a specific type of content in Scompler’s search feature, such as articles tagged for a specific campaign.

Scenario

Users may start by using the search bar or navigating through categories to find articles related to a specific campaign.

Success Rate Analysis

Suppose 50 users are tasked with finding campaign-related articles, and 45 manage to find the correct content regardless of the path they took (search or direct navigation). This gives a Success Rate of 90%. Even though some users may have taken a longer or less efficient route, they still successfully completed their goal, contributing to a high Success Rate.

In this case, the design team might further optimize the search algorithms or improve navigation links to reduce the time spent by users looking for specific content, increasing both the Success Rate and the efficiency of the task.

🟢 Afterwords

In complex products like Scompler, and most probably the one you work with, it’s essential to use both Completion Rate and Success Rate to get a full understanding of user behavior. While Completion Rate helps you identify friction points in linear processes (like multi-step publishing flows), Success Rate allows you to evaluate whether users achieve their goals even when taking alternative paths.

For example, improving Scompler’s publishing workflow might focus on raising the Completion Rate by making the interface more intuitive and reducing unnecessary steps. Meanwhile, optimizing the platform’s search functionality would focus on maintaining a high Success Rate, ensuring that users can find what they need, even if they navigate differently than anticipated.