It is the average length of time an activity occurs, expressed in minutes. So a time study participant might work for 5 hours on marketing over 10 different occasions. Therefore each occasion averages 30 minutes. Working efficiently is doing things with the least amount of wasted effort. Efficiency gets you from point A to point B via a straight line.
Inefficiency goes in circles and zigzags and gets fewer miles per gallon.
Effectiveness means doing the things that yield results. Effectiveness takes aim at the target and hits it, even if it's beyond you. Prior to beginning our time studies, we give participants a questionnaire. We ask a series of open-ended questions, to get a sense of what challenges they face. The list of responses is enlightening in how it reflects sales reps' focussed drive to gain and service customers.