For the weekly challenge. Unfortunately don't have time to polish, just can't resist the urge.=)
Illustration to old russian saying : Porcupines are stubborn birds. They are so stubborn you have to kick hard to see them flying.
To avoid loosing in translation (english is a logical language after all) - possible variation (less absurd, perhaps, that what makes it less fun ): What do Porcupines and Stubborn Birds have in common? They only fly when they're kicked.