If you lose an index finger, you can't wag it in anger or condescension.
If you lose a middle finger....Um, never mind.
If you lose a ring finger, you can't get married. (Okay, so that's not true, but that whole 'ring exchange' thing during your wedding ceremony? Awkward.)
If you lose a pinky finger, you can't pinky swear and YOUR WORD WON'T BE GOOD FOR ANYTHING!
Also, needless to say, if any of the above happens, use of the expression 'high five' will suddenly become very creepy.
So, please leave fireworks to the professionals -- and DEFINITELY don't leave it to this guy: