If an ordinary Spirit was attacked then it would be forced to defend itself and it would have to fight back especially if it was cornered and unable to avoid the conflict.
If its grade was underestimated then the person attacking it would be in a large amount of danger for doing so.
Wandering too close to an Evil Spirit that was previously thought to be a Spirit could be the one thing that could result in it being provoked enough to attack and harm someone.
Unless someone had a fairly good relationship with a Spirit then it was usually best to leave them alone and keep some distance.
It was especially true for Balancers and Watchers who could see and interact with them.
Ordinary people were far less likely to provoke any Evil Spirits or Spirits since they could not sense them or could actively take the initiative to provoke or interact with them.