Under what circumstances is it acceptable to click on your own AdSense ads?

It is never acceptable to click on your own AdSense ads for any reason. Clicking your own ads is a direct violation of AdSense policies and is considered click fraud. Google's systems are designed to detect such activity, and even seemingly harmless clicks can be flagged. The intention behind this policy is to prevent publishers from artificially inflating their earnings by generating invalid clicks. Regardless of the motivation, clicking your own ads will likely result in warnings, ad serving limitations, or even account termination. To test ad implementation or functionality, publishers should use the Google Publisher Toolbar or other testing tools specifically designed for this purpose, rather than clicking on the live ads on their website.