Planning is the activity where you decide your testing strategy, e.g., which covered issues you want to validate, how you validate them, how the resources are allocated, and when to execute the tests. Depending on several factors, you may want to prioritize some tests or focus on specific requirements.
After creating a release, you can link test runs to a release. See: Link test runs to a release in Katalon TestOps.
Once linked, the Planning tab will show you the consolidated results for those tests. In other words, it will present the latest status of each test, independent of the number of test execution you make with them.
By then, you can see the overview of your release status, which releases are ready, which are not, along with the total number of test cases and test runs linked to that release. This gives you a presentable picture to decide the readiness of a product release.