In the year 2017, there is no reason not to have a light on your handgun.  If you use your gun for home defense, it is critical to identify the threat and the backdrop.  The easiest way to do that is with a weapon mounted light.  You must also be careful not to point your gun at your family as you search.

PS: Keep your hand away from the muzzle as you manipulate the light.

Photo courtesy of Wicked Grips