Cloud migration projects have two dimensions.
First, they are short-term sprints where a project team migrates a handful of application workloads and data stores to a single or multicloud. They act independently, with little architectural oversite or governance, and last between two to six months.
Second, is the longer-term architecture including security, governance, management, and monitoring. This may be directed by a cloud business office, the office of the CTO, or a master cloud architect. This set of processes goes on continuously.