Knowing when a fire is "out"can be a tricky business and not at all as obvious as it might seem. Even if one person is successfully engaging with the flames, it is always prudent for someone else to call the FD and get them on scene. They can perform a far more professional assessment of the fire situation than any of us amateurs...

More than one fire, deemed "out" has smoldered for hours or days, finally erupting into flames and destruction.
Geezer in Chief