Was working on a client's stack and this one critical piece using ES (written by "experts" who had since left the company) was throwing an error every week at 2

Was working on a client's stack and this one critical piece using ES (written by "experts" who had since left the company) was throwing an error every week at 2 AM triggering alerts and chaos. After investigation I found nobody understood what it was doing or why. I thereby found the safest approach was to delete the ES implementation. After that everything worked and everyone was happy.