Doing some work today, the term Byzantine really describes our application some times.
Function A calls B, then calls C. Easy enough, except B also calls C. So validation in C gets called twice, except A modifies the relevant values in between the calls so one will pass correctly and the other just fails as well. Now I could straigthen this out, or just roll with it and make illogical recalculations before the function that is to do the recalculations.