Employees of Ryan's Family Steakhouse may recognize this phrase.
I used to be a dishwasher at Ryan's, and it was genuinely hard work. People would often say "Oh come on, you had a huge dishwashing machine. It couldn't have been THAT hard." Quite the contrary, it was very hard. Ryan's Steakhouse is a buffet-style restaurant, and a clean plate was required for every trip. Compound this with the fact that the place is packed during peak times, and the dishwashers get EVERYTHING. The servers toss the dirty plates, cups, etc. onto a metal ramp-like holding area, and the dishwasher takes them and sprays the majority of the food into the trash. Then, they're loaded onto trays and run through the dishwashing machine. When they emerge on the other side, they are sorted and stacked for the buffet stocker to collect them to put back out on the bar. This process repeats endlessly, and is next to impossible to complete when there is only one dishwasher. (I've been forced into doing that many times.)
Anyway, since there is really no slow-paced position at Ryan's, this phrase originates from the letters in the name of the establishment.
It's quite an apt description.