This article will help you:
- Interpret the engagement goal, which is the default goal in Optimizely Web experiments
- Choose a different goal as your primary goal
The "Engagement" metric measures the number of visitors in your experiment who click something while the experiment is running. The visitor could click a link, submit a form, or select text on your page. Think of it as the opposite of bounce rate.
Determine a Primary Goal
Instead, consider a goal that more directly affects the success or failure of your experiment. For ideas on what that might be, see our example recommendations for your primary goals or our experiment ideas for:
For technical reasons, the engagement goal cannot track every click. When a visitor clicks a link or submits a form, their browser has a brief window in between their action and a new page load during which to send an Optimizely engagement tracking call. Depending on the speed of the browser and the visitor's internet connection, this call is not always successfully made. Link clicks are more reliably captured than form submissions, but even those are not 100%.
That said, lost engagement tracking calls should occur at roughly the same rate between different variations, so the numbers are still comparable. Engagement may still be used as a proxy to determine the most effective variation if no other goal metrics are available. That is, even if not all engagement events are properly captured, they are still a worthwhile metric for comparing the relative engagement between variations.
We also try to capture any pending tracking events in a cookie and send them when a user lands on the subsequent page if that has our snippet on it. So implementing your snippet site-wide could drastically improve the engagement metric. This is true of Optimizely and most other AB testing tools.