Every CPU that isn’t pegged at 100% all the time is leaving money on the table. Some physical CPU capacity is reserved, some virtual CPU capacity is reserved, the rest goes to ultra-high-margin elastic compute that isn’t sold to you as a physical or virtual CPU. They sell it to you as “serverless,” it prints cash, and it absolutely depends on juicing every % of performance out of the chips.

edit: “burstable” CPUs are a fourth category relying on overselling the same virtual CPU while intelligently distributing workloads to keep them at 100%.