Jobst RideBike! book and Fanatyk Spokes are here!
Judging maintenance and die replacement cycles is useless unless you have a good idea about the volume of work. I regularly interface with users who have nearly no idea about the number of threadings they do. Those that claim to know are probably +/- 30%. It's time for a basic counter.
This counter is exactly what you can buy on Alibaba for $15-$20. We sourced it in some volume, cut the wire down from 20" to 6", installed a supportive wire clamp on back, and bonded a neodymium magnet to the display. It employs a sensor to count threading cycles by watching a second magnet.
To use it: