Project Selection Method

Which Project Life Cycle to use when?

Project Life Cycle

The project life cycle comprises the set of phases into which a project is organized. Depending on the organization context and any overlapping between phases, various types of project life cycle can be defined and be used to manage different types of projects, different environments they operate in, and with different Organizational structures, different management styles, different sizes, different customer needs and requirements and different Products ,Services or Results they deliver.

1. Predictive or Planning-focused Life Cycle

It is a type of project life cycle in which the project Scope, Time, and Cost are determined in the initial phases of the life cycle. It is also known as Classic, Traditional or waterfall Life Cycles. Here projects are normally organized into a series of sequential or consecutive phases and each phase focus on one type of work. In this approach requirements are defined up-front before development begins. Plans are delivered for eventual deliverables, final Product, Service or Result is delivered only at end of project timeline. It is a plan-driven life cycle, where we plan work upfront and from there work is focused on following the plan. Here expected changes are minimal because work is quite predictive and known any project scope change must be managed explicitly and usually leads to a review of the plan and formal acceptance of the new plan. Key stakeholders are involved at specific milestones only.

Predictive life cycles are chosen when the product to be delivered is well-defined and relatively extensive knowledge exists on how to build the product. This has traditionally been the most common work model but does not necessarily suit the circumstances of all projects and organizations.

2. Iterative Life Cycle

A project life cycle where the project scope is generally determined early in the project life cycle, but time and cost estimates are routinely modified as the project team’s understanding of the product increases. Iterations develop the product through a series of repeated cycles that successively add functionality to the product. This type of life cycle enables the project team to incorporate frequent feedbacks and gradually increase the experience of the team during the project as feedback helps the team to learn about the customer’s and other stakeholder’s expectations. This life cycle understands that requirements are abstract and real feedback can be achieved only when customer and other stakeholders can see some deliverable or part of the product. Here prototypes and proofs are also planned, but the outputs are intended to modify the plans created in the beginning.

Iterative life cycles are chosen when it is necessary to manage vague objectives or considerable complexity, or when the partial delivery of the product is key to success. 

3. Incremental Life Cycle

An adaptive project life cycle in which the deliverable is produced through a series of iterations that successively add functionality within a predetermined time span. The deliverable contains the necessary & sufficient capability to be considered complete only after the final iteration. In the incremental life cycle, the whole requirement, for instance, is divided into various builds which are then divided into smaller yet easily managed modules that should pass through the requirements design, implementation, and testing phases. Plans to deliver successive subsets of the overall project.

Incremental life cycles are chosen when it is necessary to manage vague objectives or considerable complexity, or when the partial delivery of the product is key to success. 

4. Adaptive Life Cycle-Incremental and Iterative

This life cycle is a mix of Iterative and Incremental development. An Adaptive life cycle is a change driven. It is an agile way of doing things as it is intended to the high level of changes. Functionalities are added incrementally, but they can be changed based on received feedback. It needs on-going stakeholder’s involvement. Iterations are very rapid usually with duration of 2 to 4 weeks and are fixed in time and cost. In this life cycle the overall scope of the project is usually broken down into a set of requirements or projects to be undertaken. At the start of an iteration, the team defines the functionalities to be tackled in that cycle. At the end of each iteration, the product should be ready for review by the customer and other key stakeholders. This type of life cycle requires teams to be highly involved and the sponsor or client to provide constant feedback.

This life cycle is used for projects where rapid changes are expected and scope is not possible to define upfront or when the value contribution is highly variable and with highly involved teams. So, change during the project is naturally handled in rapid iterations.

5. Hybrid Life Cycle

A combination of Predictive, Iterative, Incremental, and/or Agile approaches is a hybrid approach.