Mouse tests

Most mouse complaints come down to a worn micro switch. A button that has started bouncing sends two presses where you made one, which the double click test is built to catch. A button that has stopped sending anything at all shows up immediately in the mouse test. Both are mechanical failures, and neither is fixable in software.

The scroll wheel fails differently. Its encoder collects dust and starts skipping steps or reporting the wrong direction, which the scroll test surfaces as gaps and reversals in what should be a steady stream of wheel events.

Polling rate is the odd one out: it is not a fault, it is a setting. The polling rate test measures how often your mouse actually reports, which is worth checking after changing a setting in vendor software, moving to a different port, or switching a wireless mouse between its dongle and Bluetooth.