# Waterfall

### **I. What is the Waterfall model?**

**Waterfall model** or waterfall model is a model used to describe software development steps in a strict sequence and logic. This is the first model widely used in the software industry and is divided into stages, the output of the previous stage becomes the input of the next stage.

<figure><img src="https://amis.misa.vn/wp-content/uploads/2022/07/mo-hinh-thac-nuoc.jpg" alt="waterfall model" height="482" width="720"><figcaption><p>Waterfall model – waterfall model in work and project management</p></figcaption></figure>

The stages in the waterfall model are moved from high to low, one after another, and the order cannot be changed or disturbed. This waterfall-like staircase layout is the origin of the name Waterfall model.

In recent years, more agile methods like Agile have become more popular, so the popularity of the waterfall model has declined. However, it is still a work management process that business managers need to know.

### **II. Stages of the Waterfall model**

Applying **the Waterfall model** in a project does not include many complex processes. Depending on the developer or from time to time, there are some slight differences in the number and details of the steps in the waterfall model. But in general, this model has 6 basic steps as follows:

#### **1. Technical preparation**&#x20;

During this stage, businesses must collect requirements and understand the true desires of the target audience. After that, the professional team conducts discussions, analyzes feasibility, prepares documents and technical infrastructure. The above activities help businesses determine the direction for future development.

#### **2. Design**&#x20;

When there are specific requirements, the business will begin a complete design according to the description. Designs help people visualize the actual product and promptly edit it before releasing it to the public.

#### **3. Implementation**

If the design is approved, the investors will begin implementing the production project. This is a step that requires high precision in terms of specifications but does not consume much time.

<figure><img src="https://amis.misa.vn/wp-content/uploads/2022/07/cac-giai-doan-cua-mo-hinh-thac-nuoc.jpg" alt="stages of the waterfall model" height="395" width="720"><figcaption><p>Stages of the Waterfall model</p></figcaption></figure>

#### **4. Integration and Testing**

The testing or verification stage is when businesses need to ensure the product meets the requirements and has no errors. Here, the quality inspection team will thoroughly scan the product so it can be distributed to customers.

In case the business discovers major errors or requirements are not met, the project will have to return to phase one. Iteration forces the design phase to take greater responsibility and better improvements.

#### **5 . Release and maintenance**&#x20;

The maintenance phase begins as soon as the business releases the product and receives feedback from customers. In fact, this is a mandatory task because no product is perfect from the first launch.

Therefore, businesses need to have a team of experts ready to quickly handle troubleshooting and maintenance to ensure customer satisfaction. This phase will end when the product is truly completed or the technology changes so the manufacturing unit cannot repair or upgrade further.

In addition, businesses should note that they should only apply **the Waterfall model** most effectively when they fully possess the following factors:

* Implementation projects are not too complicated.
* The requirements have been clarified and stabilized over time.
* Enterprises have rich resources and well-trained human resources.

### **IV. Advantages and disadvantages of the Waterfall model**

#### **1. Convenient**

**1.1. Simple, easy to understand and easy to use**

The waterfall model is often suitable for small and medium projects. The characteristics of small projects are frequent changes in personnel and implementation methods... Therefore, Waterfall model will help everyone quickly get acquainted and keep up with work progress when there are documents drafted in advance. Keep the structure of the steps intact, and prioritize careful inspection and maintenance.

**2. High precision**

As mentioned above, the stages of the waterfall model cannot be changed, the tasks of each stage must be completed correctly before moving on to the next stage.

<figure><img src="https://amis.misa.vn/wp-content/uploads/2022/07/loi-ich-cua-mo-hinh-waterfall.jpg" alt="Benefits of the waterfall model" height="395" width="720"><figcaption><p>Benefits of the waterfall model</p></figcaption></figure>

For that reason, the waterfall model always achieves high accuracy, strictly following the design and production process. At the same time, this feature also helps the leader easily manage the entire project from design to testing and product evaluation.

**3. Flexibility**

With **the Waterfall model** , adjusting and modifying the design will be most flexible in the first steps (before reaching phase 4).

**4. Clarity**

Clarity is the most prominent element of the waterfall model. Thanks to work taking place sequentially through each stage, operations do not overlap and do not overload the enterprise's apparatus.

**5. Suitable for milestone-oriented projects**

When applying the sequential structure of the Waterfall model, managers can well organize all related work based on time deadlines. At the same time, members also quickly grasp each specific stage to prepare resources and work on schedule.&#x20;

#### **2. Disadvantages**

Besides the above advantages, **the Waterfall model** still has some disadvantages that make it difficult for businesses to apply in practice.

**2.1. Too rigid**

As mentioned above, the waterfall model does not allow modifications but must be turned around from the beginning. This rigidity is not suitable for large projects that need flexibility in each stage. Repeating processes also costs businesses a lot of time, budget and puts great pressure on both managers and staff.

**2.2. There is no backup plan**

If applying the Waterfall model, businesses often do not make contingency plans but only check and detect problems when the project is nearly completed. This approach leads to many problems arising that the business cannot resolve promptly, affecting the entire overall process.

### **V. The difference between Waterfall and Agile models**&#x20;

Waterfall and Agile are the two most typical project management models favored by businesses. In particular, Agile is a method of continuous testing throughout the product development process. This form allows activities to take place simultaneously, allowing customers to approach and give more feedback.

Specifically, the Waterfall and Agile models have the following differences:

| Waterfall model                                                                                           | Agile model                                                                                                                                                            |
| --------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Waterfall always defines a fixed timeline, the work process from start to finish is clearly planned.      | Agile is all about experimenting with different directions. Instead of a fixed timeline, the project schedule adjusts as work progresses.                              |
| Once the end goal is established, Waterfall is no longer linked to the customer in the remaining stages.  | Customers and project managers must participate and provide feedback to the product development team continuously throughout the implementation phases of the project. |
| Budgets for projects using the Waterfall method are often fixed estimates.                                | The budgets of projects using Agile methods are flexible and are estimated to prevent costs from arising.                                                              |
| Software development will be completed as a single project.                                               | Agile is a collection of many different projects.                                                                                                                      |
| The waterfall model requires a long-term plan and clear requirements.                                     | The Agile model often uses short-term planning due to quick product completion time.                                                                                   |
| Project success depends on strict implementation of requirements.                                         | Project success is based on delivering business value to customers.                                                                                                    |
| Complete requirements are clearly documented to start design, production.                                 | Requirements continue to evolve throughout the project and are identified as needed from time to time.                                                                 |
| Team members are in charge of different roles and responsibilities.                                       | Members share equal responsibilities.                                                                                                                                  |
| Change is discouraged and HR teams are often slow to respond to change.                                   | Agile projects are always ready to change and improve according to objective feedback.                                                                                 |
| Quality control activities are performed at the end of the project.                                       | Quality control activities are performed throughout the project.                                                                                                       |
