The following pictures are a repair that has failed over time. This is the top level of a parking structure and the area shown was having drainage issues. The area was not prepped properly (or at all) and the repair mortar de-bonded from the surface over time. Since this was a drainage area and water was pooling, freeze-thaw cycles accelerated the deterioration. Water got between the substrate and the repair material because of the lack of a bond between the two. The painted parking stripe under the mortar is a telltale sign that the area was not mechanically abraded. Cement based mortars will not bond to a painted surface.