Who initiated contact?

When we talk about considerations, we often do so to discuss if an offence deserved a red card or a yellow card. We seldom talk about considerations to determine if a foul has occured? We sometimes take it for granted that we know what a foul is. But do we really?

Also, when a player is hurt after they fouled an opponent, we are sometimes misled to believe that the player who is hurt received a foul. We cannot use "who is more hurt?" as a consideration to determine who fouled.

In the video below, a player who is hurt more actually initiated contact. The black team defender fairly plays the ball and receives contact from the white attacker. The referee, unfortunately, gave a free kick for the white attacking team. 

"Who initiated contact?" is an important consideration for us to use to determine who fouled.