If you're running a saas and the increased traffic comes from paying customers, you likely prefer a huge bill to downtime.
But apart from that, there's a huge benefit in saying "I'm happy to spend any amount up to X" and not needing to do any capacity planning beyond that vs. continually trying to guess what's the right % to over-provision your VMs and having downtime when you get it wrong.
But apart from that, there's a huge benefit in saying "I'm happy to spend any amount up to X" and not needing to do any capacity planning beyond that vs. continually trying to guess what's the right % to over-provision your VMs and having downtime when you get it wrong.