[MortMan]

At a certain point, mold is embedded in the building materials and must be removed and replaced, sometimes even in the framing.

[T.B. Yoits]

A building on our base had big x painted on it as condemned, and it was condemnation worthy. One day the x was gone.

A few weeks later a squadron moved into offices there because their offices in another building weren't ready. Change over the fiscal year, new offices ready, squadron moves, and the x reappears on the old building.

A month later the building is razed.