What is an SE Life Cycle Model? Systems and software engineering — Life cycle management — Part 1: Guide for life cycle management, ISO/IEC TR 24748-1:2010(E)
3.2.1 System life cycle model
Every system, whatever the kind or size, inherently follows some life cycle, evolving from its initial conceptualization through its eventual retirement… A life cycle model, then, is a decision-linked conceptual segmentation of the definition of the need for the system, its realization as a product or service, and its utilization, evolution and disposal. A system life cycle model is typically segmented by stages to facilitate planning, provisioning, operating and supporting the system-of-interest. These segments provide an orderly progression of a system through established decision-making gates to reduce risk and to ensure satisfactory progress. As stated before, it is the need to make a decision to specific criteria before a system can progress to the next stage that is the most important reason for using a life cycle model.