The exponential distribution: the good, the bad and the ugly. A practical guide to its implementation

This paper discusses the widespread applicability and mathematical tractability of the exponential distribution, as well as the profound implications of Drenick's theorem. The authors demonstrate the risks of the exponential assumption when used to represent redundant subsystems and when used within simulations. They caution about the use of the exponential distribution to represent component repairs and the failure of many to appreciate the implications of the exponential distribution's memory-less property. In summary, this paper provides insight into the good aspects of using the exponential distribution but more importantly, into the ubiquitous misuse of the most commonly implemented reliability distribution.