We examine the differences between Scrum and Waterfall, 2 representative approaches to system development, and why Scrum is emphasized in modern development environments.
1. What is Waterfall development?
Waterfall development, which moves from top to bottom like a waterfall, is a development method consisting of a sequence of ordered phases.
Characteristics
• It consists of steps such as requirements definition, basic design, detailed design, unit testing, integration testing, system testing, release, and maintenance, with clear boundaries between each step.
• The next phase cannot begin until the current phase is complete.
• Once a phase has been completed, returning to it is difficult.
• As phases are separated, work is divided between those who think and those who execute.
Benefits
• It is highly plan-driven and makes progress easier to manage on large projects.
• The personnel needed for each step can be assigned separately.
• Because documentation is emphasized, detailed specifications and design documents are completed.
Disadvantages
• Changes are difficult after a phase ends, making new requirements costly to incorporate and changes expensive.
• A long time passes between the start of a project and its actual release, delaying user feedback.
• Projects tend to run for a long time, during which user needs may change.
• Producing the enormous volume of documentation requires considerable effort.
2. What is Scrum development?
Scrum is an Agile development framework that develops software through short iterations known as Sprints.
Characteristics
• Each Sprint normally lasts 2–4 weeks, with development focused on features and tasks that can be completed within that period.
• In short cycles, users are repeatedly asked to review or use the product and provide feedback, which is then used to add and improve features continuously.
• Everyone thinks, and everyone executes.
Benefits
• It can respond flexibly to change.
• The feedback loop is short, so input from users and stakeholders can be incorporated quickly.
Disadvantages
• As Sprints continue, Scrum Team members need an understanding of the entire project, the ability to communicate with other team members, and the expertise to fulfill their assigned roles properly. This raises the difficulty of assembling a highly capable team.
• Unless the team learns and steadily carries out each Scrum process, improvised responses will increase and may instead lead to schedule delays and lower quality.
3. Why is Scrum emphasized today?
• Changes in the business environment: Today's business environment changes rapidly, and responding quickly to that change is a source of corporate competitiveness. Scrum is resilient to change and can incorporate new requirements and feedback into products quickly.
• Advances in technology: Unlike the era when hardware and software were inseparable, the spread of cloud computing and DevOps has made continuous delivery easier. In this environment, failing to use Scrum to accelerate release cycles for systems that form the foundation of operations and business creates a competitive disadvantage.
Conclusion
Waterfall and Scrum are development methods with different assumptions and characteristics. Against the background of today's rapidly changing business environment and technology, Scrum's flexibility and speed make it suitable for many organizations and projects. However, the choice between the two methods must consider factors such as project requirements, organizational culture, and resources.