Worse, you can have such needs but wind up overprovisioning because your software is tough to autoscale automatically up or down. In that case you should probably pay for dedicated, mostly static servers in traditional setups until you can’t stomach the costs of being overprovisioned anymore then go to a cloud that lets you autoscale to recover a lot of your costs. Sure, reserved instances help substantially but because it’s a cloud instances themselves can go up or down without the best SLAs (I still say I’ve had more physical servers among the tens of thousands seen go belly up than the hundreds of thousands of EC2 instances I’ve seen in my experience).

Other factors are obviously the ability to get a compute instance up immediately or because you have bad operational situations (horrible legacy DC equipment, genuinely bad admins or vendors, etc) that far outweigh the opex and capex parts of the equation and bleed into SLA, poor reputation / relationships, etc.

This does apply to non prod environments. Development/test environments that have low utilization and only run during business hours are better candidates