If you are hunting on mineralized soil, you need to adjust the Ground Balance to filter out disturbances caused by the mineralization of the soil. Ground balancing is an art and you need to try finding the point where the ground does not have any effect on your search. If your detector is set to have positive ground balance, the mineralization will tell your detector that there is a target while there actually is none. Also, targets in the soil might be masked by this effect and your detector won’t be able to find me. If a detector has been set up with a negative ground balance you might not get any signals at all. This is the worst case scenario since you are missing all kinds of good signals.
So you need to find a good and a healthy balance between those Two to get the most performance out of your detector.