This is maybe a teaser heading...
At this point, I have 8 partitions on my desktop for distros, and 6 on my laptop. One on each is unused. And I'm having trouble remembering everything I have installed when someone asks me about it. So I have hit a memory barrier, and it is the memory between my ears; and I have hit a limit of what I actually WANT to install.
I have long joked that I could fit 50 distros easily on a 1 Tb SSD, but that the time spent keeping them updated...