Unused parameters should not be removed from Unity messages.
CA1801 - Remove the parameter or use it in the method body.
using UnityEngine;
class Camera : MonoBehaviour
{
void OnCollisionEnter(Collision c)
{
// do stuff, but c remains unused
}
}The Code Quality analyzer does not detect that you've used c, and under normal circumstances, it would be reasonable to remove the unused parameter.
The Code Quality analyzer doesn't realize this is a Unity message, and therefore has no way of determining that it needs to have a specific signature to function correctly.