Just staring a loading screen essentially, most games will let you click around on the menu still and look at your skins or your settings or whatever. TF2 lets you queue mid match to find another game so you can play on a community server while you wait, and overwatch does let you do warmup DM last I remember (which was years ago so it might have changed). Can’t really think of anything else another game does off the top of my head.
For a little more context, 196’s main rule is that you need to post something before you leave. So it started with people just putting something about having to post because of the rule for the title, which then turned into just putting rule because it’s shorter, which then turned into making an actual title then putting rule in it somewhere because it’s funny.