When I choose the BEACH ON mode (GROUND menu) to detect in the wet zone of the beach, the TRACKING mode is no longer available. Why is this?

[FORUM XP]

The TRACKING mode is not available in BEACH ON mode because the PUMPING mode is much more effective and gives a more rational setting value.
On the beach, pumping (moving the coil up and down above the ground) gives a more precise measurement value than sweeping.