Abstract: Systems and methods for determining efficiency-of-use scores related to uses of a product by two or more users may implement operations including, but not limited to: computing an efficiency-of-use score associated with a use of a first physical product of a set of products by a first user and an efficiency-of-use score associated with a use of a second physical product of the set of products by a second user; comparing the efficiency-of-use score associated with the use of the first physical product by the first user to the efficiency-of-use score associated with the use of the second physical product by the second user; and providing a notification according to the comparison of an efficiency-of-use score associated with the use of the first product by the first user to an efficiency-of-use score associated with the use of the second product by the second user.