The diagram depicts a typical architecture development cycle from the TOGAF (The Open Group Architecture Framework) model. In this context, '1' represents 'Requirements Management', which is concerned with the identification, storage, and management of all requirements for the architecture work. '2' represents 'Implementation Governance', which oversees the implementation and ensures it aligns with the architecture. '3' is the 'Preliminary' phase that initiates the architectural work. Thus, the correct labels for 1, 2, and 3 in this cycle are 'Requirements Management', 'Implementation Governance', and 'Preliminary' respectively.