I work as a software developer, and we have a ticketing system. Tickets can have "priority levels", with labels like "Critical", "Highest", "High", "Medium", "Low" and similar.
It is my experience that such systems gravitate to using only three of them -- basically "Must Be Done Absolutely Right Now", "Normal" and "Will Never Be Done". And one day the first category grows too fast to get done, and the middle category also disappears.
There is a name for this phenomenon, as I recall reading about it, but I forgot what it is. "Priority compression" or something like it, but that's a useless search term as there are too many compression-related hits.
Does anybody know what it's called?