Calling OnTriggerEnter every update if something is false

I need this function to check itself again while its in the Collider of the object with the tag placed because the tag can either be place or placed. The problem is that when the object first touches this object it is always place and then the script stops checking to see if it's placed.

 function OnTriggerEnter(other : Collider){
             if(other.tag == "Placed") {
                 destroy = true;
             }else{
             destroy = false;
             }
             }