Weeks. I'm talking about multiple business weeks to spin up a new server. Sure, in a pinch I can do it in a weekend, but adding up all the stakeholders, talking it over and doing things right it takes weeks. It's a normal timespan for a significant chunk of extra power - a modern day server from Hetzner comes with over 1Tb of RAM and around 100 cores. This is also where all the reserve capacity comes from - you actually do have this kind of time to prepare.

Sure, there are scenarios where you need capacity faster and it's not your fault. Can't think of any offhand, but I imagine there are. It's perfectly fine for them to use cloud.