Agile vs Waterfall — What's the Difference?

Waterfall plans and builds a project in strict sequential phases; Agile delivers it in short iterations, gathering feedback and adjusting along the way. Waterfall suits fixed requirements, Agile suits changing ones.

The concept

Waterfall: requirements → design → build → test → release, each phase finished before the next. Changes late in the process are expensive.

Agile (Scrum, Kanban): work in 1–4 week sprints, ship something usable each time, and re-plan from user feedback.

Shape of the process

Waterfall: Req ▶ Design ▶ Build ▶ Test ▶ Release

Agile: [plan▶build▶test▶review] ×N sprints, each releasable

Practical examples

A Scrum sprint

Day 1   Sprint planning
Daily   15-min stand-up
Day 10  Review + retrospective

User story

As a shopper, I want to save my cart so I can finish later.

When waterfall fits

Regulated or fixed-scope projects, e.g. hardware or compliance systems

Common mistakes

Calling a process Agile without feedback loops.
Using waterfall when requirements will change.
Skipping retrospectives.

Key takeaways

Waterfall = sequential, Agile = iterative.
Agile handles change better.
Many teams blend both.

FAQ

Is Agile faster?

It delivers value sooner and reduces rework, not necessarily the total time.

Scrum vs Kanban?

Scrum uses fixed sprints; Kanban uses a continuous flow with WIP limits.