Step-by-Step Guide to Developing Clear Requirements

Have you ever tried to develop clear and effective requirements for a new feature, but as a result, your team was just frustrated by vague instructions or confusing expectations? As a project manager with over five years of experience in software development, I understand the importance of clearly defined requirements more than anyone. In this article, I will guide you through a practical approach to defining the requirements for a simple yet crucial feature: user sign-in. By focusing on clear, logical steps and avoiding design-specific constraints, we can create a solid foundation that ensures both user satisfaction and clarity for developers.

Part 1: Core Requirements

In this part, we’ll outline the fundamental requirements for a feature, using a Sign-in page as an example. We’ll break down the essential elements, including basic functionality, layout, and validation rules. This step-by-step approach will provide you with a clear framework for defining core requirements for any feature development.

Defining the Core Functionality

We will begin with the high-level requirement, as it provides the most insight into the value of the Sign-in feature. Typically, this requirement is already included in the feature's user story if the last one exists.

The user should be able to sign in to the X app.        

What we have so far: there is a user who wants to log in to the X app. Currently, we do not know how exactly he can do it and how the system will help him with it. However, this requirement is our starting point, and it is the most essential one because if it is not met, everything else we develop for the Sign-in feature later will not make any sense.

Also, we set aside the benefits and objectives the users want to achieve by logging into the system for now, as these are not the primary focus of defining clear requirements.

So, let’s add some specifications to this requirement to bring more clarity on how exactly the user should be able to sign in to the app.

The user should be able to sign in to the X app by clicking the "Sign in" button.        

Great. We now know that there is a button that allows users to log into the system. But where exactly is the button placed? Let's specify these details as well.

1. The X app should contain the Sign-in page.
2. The Sign-in page should contain the "Sign in" button.
3. The user should be able to sign in to the X app by clicking the "Sign in" button.        

Excellent. Now, the developers have a clear vision of what exactly you expect from them to develop and how users will interact with it. Let’s proceed.

Specifying Page Elements

Now, we need to make our Sign-in feature more advanced by verifying which user exactly wants to log in to the system to ensure that everything works properly. Typically, this involves verifying the user's login/email and password. Let's stop by email and password for now. To enable our user to enter his login credentials, the Sign-in page should include the corresponding text fields.

Now we can add two new requirements.

1. The Sign-in page should contain the "Email" text field.
2. The Sign-in page should contain the "Password" text field.        

For easier page navigation, let's place these two fields above the "Sign in" button.

1. The Sign-in page should contain the "Email" text field.
2. The Sign-in page should contain the "Password" text field.
3. The Sign-in page should contain a “Sign in” button below the “Email” and “Password” text fields.        

Awesome, let’s move forward and ensure our system is designed to process these new fields.

Implementing Basic Validation

1. When the user clicks the "Sign in" button, the system should validate the user’s email and password.
2. If the email and password are valid, the system should log the user into the associated account.        

Now, we have two problems to address:

• what action should the system take if the user enters an incorrect password or email, and
• what should happen if one or both of the text fields are empty when the user clicks the "Sign in" button?

In the first case, we need to add extra requirements to address issues like this one. The common approach for this scenario is for the system to show an error message informing the user of the invalid login credentials.

If the email or password is invalid, the system should display an error message, “Password or email is invalid,” below the “Sign in” button.        

As you can see, we've already defined how our system should act in this particular situation, what error message our system should show, and where. The more specific we are, the easier it will be for the developers to correctly understand what to create, and the higher our chance of getting the expected results at the end.

Now, let's get back to the second edge case when we have an empty field. I think the best solution would be to prevent the user from clicking the "Sign in" button until all required fields are completed. This will help us avoid the situation when we need to display an error message to the user, which is good practice for a better user experience.

1. If any of the "Email" or "Password" text fields are empty, the "Sign in" button should be disabled.
2. When both the "Email" and "Password" text are filled, the "Sign in" button should become clickable.        

In Part 1: Core Requirements, we defined the core requirements for a Sign-in feature, including functionality, page elements, and basic validation. Let’s review all the requirements we’ve established so far:

1. The X app should contain the Sign-in page.
2. The Sign-in page should contain the "Sign in" button.
3. The Sign-in page should contain the "Email" text field.
4. The Sign-in page should contain the "Password" text field.
5. The Sign-in page should contain a “Sign in” button below the “Email” and “Password” text fields.
6. If any of the "Email" or "Password" text fields are empty, the "Sign in" button should be disabled.
7. When both the "Email" and "Password" text are filled, the "Sign in" button should become clickable.
8. The user should be able to sign in to the X app by clicking the "Sign in" button.
9. When the user clicks the "Sign in" button, the system should validate the user’s email and password.
10. If the email and password are valid, the system should log the user into the associated account.
11. If the email or password is invalid, the system should display an error message, “Password or email is invalid,” below the “Sign in” button.        

Part 2: Advanced Requirements

Advanced Input Validation

In this part, we’ll take our requirements to the next level by adding more advanced validation rules and constraints. We’ll explore how to set limits for input fields, ensure data quality, and provide clear user feedback for common validation scenarios. These advanced requirements will help you build a more user-friendly feature, enhancing both system performance and user experience.

First, we need to predict the user's abnormal behavior and make the system ready for it. For example, we need to set some rules and limits for the "Email" or "Password" text fields to be sure that they are not just some random or nonsensical pasted text.

1. The “Email” text field should accept up to 320 characters.
2. The “Password” text field should accept up to 64 characters.        

This way, we avoid the situation when the user inputs a limitless number of characters into these fields and then overloads our system by processing them. Also, we need to ensure that the password and email are not too short according to our app’s rules or common standards. For example:

1. The “Email” text field should accept up to 320 characters and require at least 5 characters.
2. The “Password” text field should accept up to 64 characters and require at least 8 characters.        

Now, we need to inform the user about our validation rules:

1. If the email or password is too short, the system should display an appropriate error message indicating the minimum length required for each field.
2. If the email or password is too long, the system should display an appropriate error message indicating the maximum length required for each field.        

Detailed Field Validation Rules

Let’s make these text field validation rules even more advanced by adding the following rules:

1. The “Email” text field should require a valid email format (e.g., [email protected]).
2. The “Email” text field should not allow leading or trailing spaces.
3. The “Email” text field should not accept multiple “@” symbols.
4. The “Email” text field should only allow valid characters (letters, numbers, and special characters permitted in email addresses).        

If you're unfamiliar with these specific rules or any others, feel free to look them up on Google or ask for assistance from one of the UX designers or front-end developers.

Conclusion

By breaking down the requirements for the Sign-in feature into clear, actionable steps, we’ve built a solid foundation that guides both development and user interaction. This structured approach not only clarifies what needs to be built but also enhances the overall user experience by minimizing confusion and errors.

As we continue developing and refining our software, remember that well-defined requirements are key to creating effective and user-friendly solutions. What are your strategies for defining clear requirements? Share your thoughts and experiences in the comments below!