It's a server, so the goal is to have it run something you care about (whatever that may be) 24/7, not because you cannot live without it, but to get experience

It's a server, so the goal is to have it run something you care about (whatever that may be) 24/7, not because you cannot live without it, but to get experience with administrating a server. In contrast, your dev machine may need to be rebooted any time, or switched off if you leave for the weekend. A second defining characteristic of a homelab is that part of the rationale for owning it is in order to tinker with it, to try out new software packages, to play with tools & concepts (VMs, containers, admin and remote admin tools, KVMs). Ultimately, you may define a homelab as a "physical server setup for learning and for running personal services". Homelab operators may also take pride of the independence from large IT or cloud providers attained by operating their lab.