A fellow manager has concerns about his variance report. He says he understands that last month was not a very good one for output, but he really thought everyone put forth a good effort, so he is confused about the existence of an unfavorable labor efficiency variance. He cites as an example of the workers' effort their willingness to work extra hours to get full output, even when a whole week's worth of production had to be scrapped. He knew that his materials costs would be higher, and that overtime would make his rate variance unfavorable, but he certainly didn't think his workers had been inefficient.

write memo to the manager explaining the probable cause of the unfavorable labor efficiency variance.