Iterative vs Incremental Development: An Overview

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Although the differences may not be immediately apparent, you will be equipped to engage in discussions about iterative vs incremental development after completing this section.

Software developments that rely on successive releases of small batches, called increments, are believed to undergo incremental development. Each of these individual parts or models has its testing cycles, runtime executions, and functional evaluations. This systematic approach involves refining a version through successive additions of releases, each with specified functionalities.

Here are two quick examples:

Example 1: Let’s assume that the same e-commerce site, as discussed above, is being built using the incremental development process. Thus, the software development team will design each component separately to serve functionalities like item pages, profiles, favorites, checkout, etc.

The team releases its preliminary draft or increment consisting only of the profiles and enlisted products. These components do not have any functionality of their own. Next, the second increment comes where testers can access the checkout section and individual shopping carts. Like this, the system tool keeps on getting assembled until the design appears to be flawless to the client.

Example 2: For banking apps, when the incremental model is followed, instead of releasing the software in parts, the development team releases a final version. Before that, the team members continuously strive to optimize performance and elevate user experience. As a result, the incremental stages successively involve incorporating basic account information, transaction view window, fund transfer section, push notification features, and much more.

To thoroughly understand the iterative vs incremental development model, you can register for a high-quality online PMP course. These programs allow learners to complete the curriculum at their own pace and introduce them to a professional business environment under the guidance of industry experts.

Plus, you get more iterative vs incremental development examples for effective case studies.

Why is Iterative and Incremental Development Important?

The iterative vs incremental PMP Agile empowers project managers to reap the effects of efficient project management. Both are handy in making changes on-time required for a project. Therefore, the engineers and marketers do not have to wait till the end when it becomes too late and additional resources are wasted.

The iterative approach refers to developments that are cast on an ongoing pattern. On the other hand, incremental development ensures higher-quality output via discrete launches. It is a major belief that iterative approaches aid better product engineering and contribute towards shorter cycles. We will try to find the truth as we dive deeper into exploring incremental vs iterative Agile.

Iterative vs Incremental: Comparison Table 

In the table provided below, we have listed the parameters that differentiate iterative and incremental development cycles.

Parameter	Iterative	Incremental
Approach	The releases or sprints result in fully functional releases, albeit with limited features.	It is a continuous development process where the team works towards finishing the final product by completing small, incomplete parts.
Completion Time	Sprints are fast-paced to complete project milestones as per pre-decided deadlines.	The incremental approach takes more time to develop a product.
Product Quality	Product versions launched in the market may lack significant functionalities as the team aims to incorporate improvements over time.	Typically, the client receives a significantly higher standard product after just the first cycle.
Risk Mitigation	Iterative development processes reduce common risks associated with a software development process.	Incremental approaches work well with highly experienced teams as the method attracts more risk.
Error Identification	Finding and rectifying errors are easier as iterations take place independently.	Even though incremental phases are completed, engineers cannot swiftly modify the functionalities because they must wait for the final product.
Adaptability	It is preferable to go with iterative PMP when the project is more likely to face unforeseen challenges.	Incremental models are less flexible, and changes can cause unwanted project delays.
Client Engagement	Client engagement is more important as product development prioritizes opinion sharing.	User engagement is minimal.

In the upcoming section, we elaborately explain the differentiating factors of PMP iterative vs incremental development models.

It will help you understand the nitty-gritty of project requirements in the new era of technological advancements. Also, you can grab an idea of how to run development cycles for faster market entry.

Difference Between Iterative and Incremental

Here you can get a brief rundown of the Project Management training course content:

• Iterative vs Incremental PMP: Upfront Planning

When planning the coding approach, incremental development phases require thorough upfront planning. This ensures a solid structure of the execution plan and precise scope detection.

Iterative development plans are very flexible. The project requirement sheets only define the high-level demands. Contrarily, the specifics start emerging as the testing starts.

• Iterative vs Incremental: Life Cycle

The iterative development method progresses much more swiftly as only the key functionalities are checked over the iterations. On the other hand, teams involved in incremental development separately focus on individual portions of releases. Thus, it generally requires much more time.

• Iterative vs Incremental: Change Embracement

Overall, project scheduling and deployment may be affected when team members attempt to introduce changes in an incremental approach. Thus, considering this note, many firms prefer iterative development. This encourages lessons and feedback sessions to begin with the upcoming iterations.

• Iterative vs Incremental: Team Experience

When engaging in live projects that involve iterative vs incremental PMP Agile approaches, you will notice a stronger tendency toward an incremental mindset. This is because beginners find it more manageable as the plans that need to be executed are clearly laid out.

Iterative executions call for mature professionals as the development process is bound to run into states of ambiguity multiple times. Hence, wherever the scope for feedback collection is limited, it is better to go with incremental development.

• Incremental vs Iterative PMP: Project Costs

The incremental method is cost-effective as the team needs a single budget for the final output. Therefore, project costs can have slight alterations if the scope changes. Meanwhile, the iterative method can sometimes prove to be much more expensive as every iteration needs separate funding.

• Iterative vs Incremental: Feedback Usage

Stakeholder inputs are the only key drivers in incremental development plans. Also, these feedback sessions take place at the end of each increment and do not occur in a continuous fashion like iterative development. Thus, feedback solely plays a vital role in framing and designing iterations.

• Iterative vs Incremental: Documentation

Documentation is well-defined only in incremental development. It is a major distinction handled by developers in the context of iterative development vs incremental development.

You can learn more about the documentation presets in KnowledgeHut’s certification on PMP. It is a round-the-clock instructor-led training module featuring a replica set of PMP questions taken from PMI's copybook. So, you can consider enrolling for guaranteed success for your upcoming PMP exam prep.

Advantages and Disadvantages of Iterative vs Incremental Development

For first-time iterative vs incremental PMP method learners, we have listed the pros and cons of each approach here:

Iterative Approach

Developers pick this method to cater to complex project requirements that need changes on the go.

Pros

• Iterations utilize the changing priorities and are thus more flexible
• User feedback can be very useful in refining the development cycle
• Error-making chances are drastically reduced as team members eliminate the risky elements early
• As testing and feedback collection occur continuously, there is room for quick improvement

Cons

• Fragmented focus can, at times, change the purpose of the final product as developers constantly shift their objectives
• Iterations involve repeated testing, implementation, and refinement, thus taking a lot of time
• Scope and feature creep can be uncontrolled due to a lack of upfront plans

Incremental Approach

When client requirements are crystal clear, the incremental development process becomes the way to go for most agencies.

Pros

• Release dates, timelines, and feature scheduling are all much more predictable
• Risky increments or chunks of the project can be separately analyzed to avoid a complete project halt
• The incremental development plan is cost-effective
• It has clear documentation of steps from the beginning

Cons

• Flexibility is hindered as agile principles are not that much considered after the initial draft is made
• A delay in launching one increment can push all the upcoming deadlines (also referred to as cascading delays)

How Are They Similar?

Both iterative and incremental development strategies contribute to numerous project benefits. In terms of risk management, the first approach seems more practical. However, incremental development also helps manage risks in the context of project cost and ambiguity.

Also, when it comes to elevating business value within a short timeframe, a combination of both, i.e., hybrid development, directs the system architecture. Thus, project managers cannot completely ignore both while handling big projects.

What Should You Choose Between Iterative and Incremental Development?

Here are some factors you need to consider before deciding between iterative and incremental PMP:

• Project Size and Complexity

If the project looks too complex, then iterations can solve the issue. Under such circumstances, the developers cannot decide on set documentation, which is the case for the incremental approach.

• Team Expertise

When the team members have limited Agile experience, incremental development suits them more. It eliminates the uncertainties that come with rapid modifications and repeated prototyping.

• Available Resources

The scope for adapting to new features is considerably high in iterative development. However, planning and allocating resources is much more rigid in incremental development.

• Timeline

Iterative development plans should be used in case the project deadlines are too tight.

Conclusion

Before you decide on any solution, it's really important to take a deep dive into what the project is aiming to achieve. That means not just looking at the goals themselves but also considering what your team can handle, how much support your organization can give, and where you might be able to be flexible along the way. Understanding the difference between iterative and incremental project management approaches is key here. Each has its own good and bad points, and finding the right mix is crucial. Being comfortable with both methods lets you pick and choose the best bits for your project.

When you're dealing with a project that will take a while to finish, careful planning is vital. That means not just following one set of rules but being ready to blend different approaches as needed. Flexibility and adaptability are your friends here!