- What scale you're operating at.
- What vendor you've found that can provide you with 100 leased servers in 2-3 days while costing less than a cloud provider and not requiring you to maintain your own routing/switch/etc infrastructure.
- How you see a dedicated vendor providing managed leased server hosting, network services, on-hands management, etc, as to be genuinely different from a cloud provider -- other than requiring a significantly longer turn-around on provisioning and management tasks.
- How expensive (and for what length) the lease terms are on that server hardware. I've yet to find a quality managed hosting provider that will lease hardware at terms that come close to matching the pricing of either in-house maintained or EC2 provisioned servers).