Sill damage can occur for many reasons that I will explain in future posts.
This building is a church in Eastern NY. Sometime in the past the stone foundation was exposed to add a layer of cement to the exterior. The cement was placed on top of the original stones and against the grade sills. Over time it began to take on water that ran down the wall and found its way behind the clapboards and trim boards. As a result the sills on the entire church failed. There was no evidence of flashing at the lower wall that would have helped considerably or would have eliminated the condition entirely.