It doesn't go away. If anything it gets much worse as the call progresses. I was working a two story residential job that IC had pulled everyone out to go defensive. The upper floor was just about gone and the truck was flowing big water. I was the officer on a 2 1/2 exposure line. SOP's tell us that if operations has gone to defensive all units must operate out of the collapse zone. Now I don't know what possessed me but at some point I thought it would be a good idea to ventilate a bay window on the second floor. Just like i have done several times before I reached down and picked up a rock and threw it at the window. It didn't break, so I moved closer and grabbed a brick. The brick worked. The window broke and as I turned to walk away from the house my crew shouted and ran towards me. My reaction was to duck and move. This probably saved my life. The front brick vernier wall collapsed and just missed my by about a foot. I survived my brush with death and have learned a valuable lesson. If you are in defensive mode STAY OUT OF THE COLLAPSE ZONE!