The iterative software development model is the approach in which the process of developing a complex application is broken into smaller parts. The iterative SDLC model refers to a unique implementation of software development projects in which it starts with simple processes and features before progressively moving to more complexity and a broader feature set toward the completion of the system.
This is one of the simplest models to develop software, which gives certain flexibility to changes or enhancements of features in the actual span of the project, besides the predetermined core software requirements. In this tutorial, let’s take a closer look at the iterative model, its application within a project, as well as its advantages and disadvantages.
1. What is the Iterative Software Development Model?
The Iterative software development approach was used in projects as early as the 1950s in a wide range of software applications, from modern web applications and high-performance gaming clients to the United States Department of Defense’s software acquisition standard. This model is generally a big evolution over the traditional waterfall model of the past, which breaks the whole process into smaller “iterations” that contain planning, design, development, and testing steps.
Different from the waterfall model, which focuses on a stringent step-by-step process of development stages, the iterative process is a cyclical process that adds features one by one, creating a working product at the end of each iteration, and increases overall functionality at the end of each cycle.
Features of the Iterative Software Development Model
Breaking down each stage of the iterative software development model helps enterprises and outsourced teams understand how the cycle progresses step by step. The following sections outline the major features of this model and explain how each contributes to efficient, adaptive software delivery.
Stage 1: Initial Planning
At the outset, the project team and stakeholders establish the vision, objectives, and scope of the first iteration, thereby creating the baseline for subsequent cycles. They decide on high-level requirements, select priority features, and allocate resources while recognising that this plan will evolve. It is important to document assumptions, identify early risks, and set up feedback mechanisms to support iteration.
Stage 2: Requirements
In this stage, the team refines the initial planning to define detailed functional and non-functional requirements for the upcoming increment, capturing user stories or use cases and acceptance criteria. Developers, testers, and business stakeholders collaborate to ensure a clear understanding and alignment with business goals. The team also ensures that the requirements are measurable and testable so that iteration success can be assessed effectively.
Stage 3: Analysis and Design
The project team analyses the validated requirements and then defines the architectural and component design for the increment, including interfaces, data models, and system modules. This design is tailored for the iteration’s scope, and the team ensures that modules are modular, extensible, and aligned with longer-term architecture. It is crucial to keep the design lightweight enough to allow evolution in later iterations, while still maintaining a solid structural foundation.
Stage 4: Implementation
Developers write the code for the selected features in this iteration, following coding standards, adhering to the design, and integrating modules into a working build. The team collaborates closely with testers and uses version control to manage changes and ensure quality from the start. The key focus is on producing a functional increment rather than a full system, which allows early delivery and feedback.
Stage 5: Testing
During testing, the team validates that the implemented increment meets the defined acceptance criteria, conducts unit tests, integration tests, and system tests specifically for this iteration. Testers work alongside developers to find defects early, demonstrate the value of the increment, and confirm that the solution is ready for delivery. It is essential to include real user feedback, automation where possible, and a readiness review to ensure that the increment is stable.
Stage 6: Evaluation
At the conclusion of the iteration, a review meeting is held where the team demonstrates the increment to stakeholders, gathers feedback, assesses performance against goals, and determines what changes or enhancements are required for the next cycle. The evaluation phase drives learning, improvement, and prioritisation for subsequent iterations. It is necessary to update the roadmap, adjust scope, and reflect on team practices to ensure continuous improvement within the iterative model.
Stage 7: Deployment
Once the increment passes evaluation, the increment is deployed or released in production or a staging environment, making the functionality available to users and collecting further feedback from real usage conditions. The deployment step ensures that operations, user training, and transitional activities are managed for the iteration’s output. It is important to monitor the release for any immediate issues and support user adoption responsibly.
Features of the Iterative Model in Software Development
Advantages & Disadvantages of the Iterative Software Development Model
Advantages
Early working increments: The model enables delivery of functional pieces early in the project, which allows stakeholders to review actual working software instead of abstract specifications.
Better risk management: By breaking the project into cycles, teams can identify and address major risks in earlier iterations when the cost of change is lower.
Flexibility to change: The iterative model allows evolving requirements and design adjustments as the project progresses, which helps to adapt to business or user changes.
Improved product quality through regular feedback: Frequent cycles with working increments allow testing and user input early and often, which enhances the quality and relevance of the final product.
Disadvantages
Increased resource demands: The iterative model can require more planning, coordination, and repeated work across iterations, which may increase cost and management overhead.
Difficulty in defining final scope and timeline: Because the model evolves through iterations and accommodates changes, it may be challenging to accurately forecast budget, timeline, and deliverables early on.
Architectural issues if initial design lacks full coverage: If the system architecture is not sufficiently defined early, successive iterations may encounter integration problems, inefficient structure, or technical debt.
Not ideal for very small or rigid-scope projects: For applications with very fixed requirements and minimal change, the overhead of iterations may outweigh the benefits, and a more traditional model may be more efficient.
When to Use the Iterative Software Development Model
The iterative model is widely applied across industries such as enterprise software, fintech platforms, e-commerce systems, and digital transformation initiatives. Below are common cases where your business should consider using the iterative model.
1. Projects with evolving or uncertain requirements
When initial requirements are unclear or likely to change due to user feedback or market dynamics, the iterative software development model gives your organisation the flexibility to refine each version, incorporate insights and stay aligned with changing needs.
2. Large-scale systems with modular architecture
For enterprises building complex systems that can be divided into modules or components (for example a fintech backend, a CRM platform, or a multi-tenant SaaS solution), the iterative model supports manageable development cycles, integration of components and gradual evolution of the overall system.
3. Products requiring frequent releases and feedback loops
When your business strategy emphasises rapid value delivery, user-driven enhancements, and continuous improvement (for example in agile outsourcing, digital customer experiences, or mobile apps), the iterative software development model helps release working increments quickly and adapt based on real use.
4. Outsourced software development with incremental delivery
If your enterprise engages an external partner for software outsourcing and you prefer a delivery model that allows review of working increments, progressive scope refinement and collaborative decision-making rather than a fixed-scope upfront contract, then the iterative model is a strong fit for your engagement strategy.
By embracing the iterative software development model, enterprises can deliver working software in cycles, gather feedback early, and adapt to changing requirements while reducing risk. For businesses seeking flexibility, continuous improvement, and a scalable delivery framework, the iterative model offers a strategic advantage—so if you are planning a large or evolving software project, adopting this model can enhance both speed and quality.
In case you are looking for a partner to assist you throughout the process, Newwave Solutions is always by your side. Contact us and enjoy the professional software development services we deliver to help you build your ideal software products/ services.
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