So you’re looking to improve your Facebook ads.
That's a fairly loaded thing to tackle, as there could be many reasons why an ad doesn’t do well.
Maybe your ads are doing “okay,” but you know they should be doing better. Or maybe they aren’t doing so great, but you’re reaching your “whole” audience. Whatever the case is, Facebook does a great job pointing you in the right direction with their ad relevance diagnostics.
You’ll have to do some tinkering, but we have some insight that should help you.
Simply put, Facebook’s ad relevance diagnostics assess ad performance over a date range.
If you aren’t meeting your advertising objectives, you can use these diagnostics to understand whether adjustments to your presentation, post-click experience, or targeting could improve performance.
That being said, it’s important to know that high relevance diagnostics rankings should not be your primary goal. High rankings don’t guarantee increased results.
“High relevance is correlated with high performance, but it’s not always the reason for high performance. As such, use ad relevance diagnostics to diagnose underperforming ads – not to optimize ads that are already meeting your advertising objectives.” - Facebook
The metrics that Facebook uses to gauge ads are:

These are default columns in the Performance column preset but must be added manually to custom column presets. Also note that to ensure accuracy, diagnostics aren’t available for ads with fewer than 500 impressions.
Before August of 2019, Facebook reported ad relevance differently. This shift to a dynamic diagnostics approach came after years of Facebook assigning a numerical value to an ad’s overall performance (relevance score). Both systems use perceived quality and audience feedback to calculate ad effectiveness. They’re functionally similar, but the new one reports insights in a more actionable way. Otherwise, not much has changed.
Measuring ad relevance helps Facebook balance their ad auction system, and reporting those results helps advertisers refine their ads.
When troubleshooting an ad that isn’t meeting your advertising objectives, you can review ad relevance diagnostics to find any outstanding weaknesses.
Consider the following before reviewing your relevance diagnostics:

Facebook’s Ad Relevance Diagnostics is a nifty bundle of three ad performance metrics that can help advertisers refine their ads. They do a great job highlighting where your underperforming ads could use improvement.
Remember, diagnostics rankings have no intrinsic value and are not to be used for post-goal optimization. Instead, use them as insight to optimize ads to meet their objectives.
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