The Waterfall Model

Chapter 4: Project Delivery Models

The Waterfall model is the traditional approach to enterprise IT project delivery, characterised by linear, sequential phases:

Requirements: This phase establishes the foundation by collecting and documenting project specifications. It involves stakeholder engagement to accurately capture needs and expectations, culminating in a requirements document outlining the product standards.
Design: This involves using the project's solution architecture to create detailed plans and designs, specifying the system's structure and the components to be developed.
Implementation: This process transforms the design documents into functional software, including coding and assembling software components and subsystems, resulting in a working system ready for testing. Testing: This focus is on quality control, and the system is thoroughly checked through unit, integration, system, and acceptance testing to identify discrepancies from the requirements and specifications.
Deployment: Releases and integrates the product into the live environment, encompassing user training, data migration, and system configuration, marking the transition from development to operational status.
Maintenance: Addresses emerging issues, implements system enhancements and applies updates based on user feedback to ensure the system remains practical and relevant.

Each phase is structured with specific deliverables that are reviewed and approved before progressing. The main advantage of the Waterfall model is its clarity in tracking progress through predefined milestones and staged phases. This structured approach builds confidence in managing timelines, budgets, and delivery risks.

Navigating the Waterfall model's phases requires a dedicated team, each fulfilling a specialist role:

Project manager: Oversees day-to-day operations to ensure the project remains on schedule and within budget.
Business analysts: Elicit, document, and prioritise requirements that align with project objectives while supporting business needs.
System architects: Create system blueprints, integrating hardware and software within the constraints of enterprise architecture to satisfy requirements.
System designers: Conceptualise the system architecture and design components based on the requirements. Developers: Convert the system design into a functional product, adhering to requirements and design specifications.
Testers: Conduct comprehensive testing to ensure the product meets all specified requirements and is defects-free.
Support and maintenance team: Resolve operational issues post-deployment to ensure the project functions effectively and meets user needs.

Product Quality in the Waterfall Model

The Waterfall model emphasises the expectation that the entire product will be delivered by the project's conclusion, promoting extensive coverage of features and requirements. As deadlines approach, limited time can make it challenging to develop each feature thoroughly, potentially compromising overall quality and leading to a higher incidence of defects in the live environment. This may result in initiating an enhancement project to address the initial project's shortcomings.