Why do 'fly's always vanish when you get the swatter or fly spray?

Question

Why do 'fly's always vanish when you get the swatter or fly spray?

Answer 1

maybe they are clever?

Answer 2

The FLIES  can see you coming!!

Answer 3

Anything that knows how to walk upside on the ceiling has got to be way smarter than mere humans (or hobbits)

Answer 4

They have those multifaceted eyes that can see you coming.

Answer 5

I wish I had their ESP.  Try using "Bronco"  It's more of a repellent.  I spray it on me, my dog, the table top, chairs everything (outside).  Then I have a fly-free zone.  It's an equine fly spray.  You can get is at any feed and seed store. Stuff really works.

Answer 6

Must be Murphy's law. No, they see the swatter and fly.