Answer.

Initially, analysts recorded requirements separately, not always considering the interrelationships between them. This worked for small systems, but in large IT projects, the complexity of relationships between requirements increases dramatically: data dependencies emerge, integrity violations occur, contradictions arise, and cascading changes increase the risk of failures.

Problem — The absence or implicitness of connections between requirements leads to missed functional blocks, bugs, blocking tasks, and uncoordinated teamwork. Often, one requirement changes while related ones lag behind, causing issues in product functionality.

Solution — Utilizing the practice of explicit modeling and mapping of requirement dependencies. This involves using diagrams (such as a traceability matrix, ERD), specialized tools (Jama, Jira linking, DOORS), clearly documenting "parent" and "child" requirements, and their impacts on test scenarios, architecture, and user stories. Transparent documentation of all dependencies and notifying stakeholders of every change related to connected requirements is essential.

Key features:

Introduction of a traceability matrix between requirements, test cases, and tasks
Use of automated notifications for changes (change impact analysis)
Visualization of the structure of requirements and their relationships on diagrams

Trick questions.

What happens if dependencies are not specified in requirements?

Answer: Critical connections may be missed (for example, one requirement cannot be implemented without another), blockers will emerge, client dissatisfaction will arise, and additional testing loads will occur.

Is it enough to gather the dependency map once at the start?

Answer: No. The dependency map must be maintained throughout the project lifecycle. Any change in a requirement can affect all related ones.

Can dependencies only be direct (A depends on B)?

Answer: No. In real systems, there are often cross, cyclic, and transactional dependencies, as well as influences through shared resources or integrations.

Common mistakes and anti-patterns

Ignoring explicit modeling of dependencies (everything is kept "in mind")
Modeling only direct dependencies, ignoring transitive connections
Insufficient visualization of structure of requirements for the team

Real-life example

Negative case: In an e-commerce project, the dependency between different payment channels was not reflected. When one module was changed, a failure occurred — some orders were not processed.

Pros:

Minimal initial modeling time

Cons:

Non-obvious system failures
Increased number of incidents in support

Positive case: For each business requirement, the related technical requirements were documented, and a traceability matrix was created. Automated notifications were sent to all stakeholders upon changes.