The role of the requirements in software development

When you want to develop your product idea, it is not enough to have the idea itself. You can ask the development team to develop an application where people can buy clothes, but they can not create software according to such a  blurred description. Development of your future product concept requires a more in-depth approach which includes gathering of product’s requirements by the software development team.

Types of requirements

1. User requirements

User requirements document how a potential user will use the product with all the problems and needs the user can face during his interaction with the product. The purposes of the requirements are to foresee:

• how and what the user expects from the software;
• how the user will interact with the product;
• what needs the user may have according to these requirements.

One of the ways to get core information is by launching the MVP of your product and then gathering users’ feedback. Here you have feedback, and a list of wishes from the target audience. But still, there is work for business analysts because you do not receive well-written requirements from users but only their wishes in common. A Business Analyst has to understand, analyze and create user requirements for the product.

2. Software requirements

Software requirements define functions and features to develop. This is the stage when business requirements transfer into the description of certain features and functions from the technical perspective, so the development team clearly understands what to develop

Typically there are the following types of software requirements:

• functional requirements which encompass the system’s behavior and what the system has to do and what not;
• non-functional requirements which cover such aspects as usability, performance, scalability, security, and portability.

3. Business requirements

Business requirements define the product’s business needs, what benefits they will result in, and criteria or standards to evaluate the success.

To get proper business requirements, make sure they are:

• Verifiable – meaning you can check if the requirements can be implemented, for example, if it is possible to realize the requirement by the technical side of the product.
• Precise – so the exact requirement is responsible for solving a specific problem. It also can be stated in the recruitment description.
• Comprehensive – covering business needs complexly, including every aspect of the specific need.

Requirements creation process

1. Elicitation

It is the process of describing the way requirements will be gathered. During this step, there is an opportunity to define the scope and prioritize user needs and your needs as a client

2. Classification

The name speaks for itself. It is the process of classifying requirements into different types which we described above.

• Functional/non-functional
• Imposed/derived/emergent
• Priority
• Scope
• Product/Project
• Volatility/Stability

3. Validation

Validation is an important step where you confirm with the stakeholders that all the requirements meet all the product’s needs. The requirements are useless for the product if they are not validated.

4. Prototype usage

Prototypes are a great way to check core functionality and requirements in action.

5. Development & Implementation
6. Negotiation

It is the process of discussion with the stakeholders when you negotiate all the controversial aspects of the requirements to satisfy every stakeholder’s needs. All the stakeholders can suggest their vision and changes, so you can create the requirement to satisfy every side.

7. Verification

The final step is verification. It is conducted when the final product is ready for usage by its potential users.

The verification step is conducted by the acceptance test. The main goal of this test is to check if the software solution developed according to the written requirements and satisfies user needs and if the system behavior works as intended to behave in a certain situation.

When functional features are easier to verify through testing, the non-functional features require a more complex approach for testing. To verify non-functional features, you can simulate the situation to see if the feature works right as was written in the requirements and meet all the needs and expectations.

Criteria of the accurate requirements

To avoid committing common spread mistakes and not waste time on them while writing requirements, we have chosen a few tips that you can use as a checklist when developing requirements. Following them will increase the quality of the requirements.

1. Clear and understandable from first sight

It is highly preferable to write the requirements using understandable language, without specific terms, slang, or other words that can confuse anyone who will read the requirement

Also, keep in mind that requirements should not have multiple meanings. When you write requirements and understand that the term, name, or whole sentence can be understood differently, even a little bit, by different groups, you must rewrite it or clarify the moment. Only in this case, the requirement will have a single and correct interpretation.

2. Accurate and detailed

Do not describe requirements just on the surface. Go deeper in detail as much as possible so those who read them understand everything clearly and will not have any additional questions. If you are doubtful the requirements cover all the details and aspects, ask someone else to add what they see the requirements lack, for example, the project manager or someone from the development team.

3. Testable and measurable

When the development team developed a feature according to the requirements and implemented it to the software, how to say that it successfully implemented? And how to measure if the feature performs its main task and meets the needs? That is the reason why it is important to include a success measure when creating the requirements.

Incorrect requirement formulation:  The search engine should show the results fast.

Correct requirement formulation: The search engine should show the results in 3 seconds after clicking the search button.

Only by making the initial requirements more specific and detailed you’ll be able to see if the developed solution meets the requirements or not.

If you want to develop perfect software, you cannot go along without high quality requirements. Remember that requirements should be clear, understandable and cover all the aspects of the feature it describes. At ASD, we always stick to the initial requirements, and always verify those throughout the whole development process. That is what makes a great contribution into the efficient delivery of our clients’ products.