> In normal operation of EC2, the DWFM maintains a large number (~10^6) of active leases against physical servers and a very small number (~10^2) of broken leases, the latter of which the manager is actively attempting to reestablish.

It sounds like fixing broken leases takes a lot more work than renewing functional leases? Funnily enough, there is already an AWS blog post about specifically preventing these types of issues: https://aws.amazon.com/builders-library/reliability-and-cons...