In the before-times, when Raspberry Pi CM5s were (relatively) affordable, I built a number of Pi clusters ( example ), and one of the most annoying parts of the build was flashing Raspberry Pi OS to all the Pis.

One, two, or even three Pis isn't a big deal, but once you hit 4+, the process of plugging the Compute Module into a carrier board, plugging that into a computer, managing Raspberry Pi Imager, and trying to match up details like a hostname, MAC address, and the physical Pi itself, gets annoying.