Idempotence is the property of a software that when run 1 or more times, it only has the effect of being run once. I’ll describe a process I’m making at work, and describe the problems that idempotence will help avoid.

This is a nice, simple example (charging dormant customers a monthly fee) of how a slight change to the way you tackle a feature can make it idempotent, which is most definitely something you want your software routines to be.