Each rule has its own logs page where we record everything that you need to know about its activity. To open the logs hover the mouse over the rule's name and click on the logs button on the right hand side:
Every rule works on a schedule. In this example the rule is doing the checks every 15 minutes and hence it records the logs with the same frequency. Each row represents a separate time when the rule ran and did or did not do something. The green row is when the rule triggered, you can see how many items (campaigns, ad sets or ads) were affected by the rule in the affected items column:
You can also look at the data Revealbot pulled from the Ads Manager and see which conditions in your rule were met and which weren't. Hover the mouse over the line you're interested in and click Details button:
There you will see the list of all items checked by that rule at that exact time and date. It'll also include the values of the metrics you selected in the rule, it'll highlight the matched conditions in green when you hover the mouse over the rows as well and more:
If you're wondering why a certain ad set wasn't affected by a rule you can use the ad set ID search there, see the Search logs by item ID in the top right corner on the screenshot above.
The logs usually contain all the answers but if you struggle troubleshooting something we're always there in the chat, just let us know!