Several life measures are defined in the literature. This paper deals with defining a service life measure for a component with lognormal life. It is proposed to set the service life at the inflection of the failure rate function. The service life defined in such a way is a function of the shape parameter. This implies that the shape parameter reflects the product quality. Based on the value of the shape parameter, the component quality can be classified and the component can have different quality improvement or maintenance strategy.