GetAxis difference between mobile and mouse

I'm using the simple script below to rotate an object in 3D world space. It does work correctly while dragging on mobile and in the unity Game view. And when clicking the mouse around the screen the object does not rotate until you start dragging the mouse around. The issue is that simply tapping the screen on mobile causes the cube to instantly rotate, and then the dragging works. Why is this happening on mobile only, and does anyone have suggestions to fix the issue?

 public class RotateDemo: MonoBehaviour
 {
     public float rotSpeed = 100;
 
     void Update()
     {
         if (Input.GetMouseButton(0))
         {
             float rotX = Input.GetAxis("Mouse X") * rotSpeed * Mathf.Deg2Rad;
             float rotY = Input.GetAxis("Mouse Y") * rotSpeed * Mathf.Deg2Rad;
 
             transform.Rotate(Vector3.forward, -rotX, Space.World);
             transform.Rotate(Vector3.right, rotY, Space.World);
         }
     }
 
 }