Not necessarily. An excessive amount of granules are applied during the shingle manufacturing process to make sure that the asphalt on the roofing sheet is completely covered. It is important to completely cover the sheet with granules so that the asphalt is not exposed to ultraviolet light.
The granules are then pressed in. Due to the excessive amount of granules applied, some of the granules are only held loosely in place. Most of the excess granules are removed by the shingle manufacturing process, but some of these granules do get packaged with the shingles. These excess granules are known as “hitchhiker” granules.
“Hitchhiker” granules will typically come off during the first few years of shingle exposure on the roof. They usually will be found in gutters or at the bottom of downspouts. The loss of these granules is normal and does not affect the performance of the shingle. Granule loss only becomes a problem when much of the asphalt becomes exposed on the surface of the shingle.