Sometimes you want to test some wacky ideas.
Sometimes (all the the time) you shouldn't take production down with your wacky ideas.
For everything else there's Mast homelabs.
I started to build a homelab for two reasons:
As my homelab matured, it became more and more crucial that I did not take down my servers with my experiments. In the future, maybe I will expand my homelab for higher availability. However, my electicity bill and my wallet do not agree. To avoid downtime, I also have a whitebox server solely for testing wacky ideas.
pfSense
FreeNAS
Debian