Do ferrets intentionally take their harnesses of?
Well, it is not because they feel a "need to escape to the wild" or because "they are not truly domestic animals". In reality, there are a few different reasons why ferrets slip their harness.
1) SCARED! If your ferret becomes startled, they may attempt to slip their harness in order to get to safety
2) YOU'RE GOING TO WRONG WAY! Your ferret is tired of not being able to go where he wants... he figures that if he takes this lousy thing off, then he can go explore that shrub over there or this bit of garbage over here properly, without you interfering (he is not aware of the danger that the situation poses)
3) I'VE HAD ENOUGH, TIME TO GO HOME NOW! Your ferret is tired and done with this game. He wants you to take him home, or he will go home without you.