Liked the puzzles and copied here for my reference.
Puzzle #1: Create flexibility by being less flexible: Moving capability to the cloud might provide flexibility such as storage elasticity and pay-per-feature options, but may come at the price of vendor lock-in and limiting feature sets.
Puzzle #2: Determine the cost of an existing IT solution: Cost of existing application (hardware and software) is compared against the cost of running a technology service. How to understand and calculate the true costs that come from labor, utilities, backups, disaster recovery etc and allocate the appropriate costs for each service being considered for the cloud.
Puzzle #3: Simplify the environment by introducing more complexity: One claims to eliminate the complexity of developing, managing, and hosting the solution internally. However in this process, supporting disparate vendor solutions adds a new level of complexity and there are challenges in getting these applications to interface with each other.
Puzzle #4: Provide assurances of sustainability in a domain of uncertainty: With the benefits so compelling, it can be hard to resist moving forward to cloud, but the challenge is to receive and provide assurances to already skeptical stakeholders.
Puzzle #5: Maintain security while reducing it.: By moving services to the cloud, you may essentially be outsourcing your security.