PCI compliance
We got marked down the other day for some of our Server 2016 instances, as they hadn't got the latest patch applied - fuckwits.
You can't win, can you. You either roll-out patches immediately, and risk being an unwitting beta-tester, but be compliant, or you wait, and test, and wait for Microsoft to fix it, and then get called out for being cautious.
Gaaaaaah!