Agile methodology is a flexible, iterative approach to product development that emphasizes collaboration, customer feedback, and continuous improvement.

Instead of delivering a final product all at once, Agile teams work in short cycles called sprints, where they build, test, and release small, usable parts of the product. This allows teams to adapt quickly to changes, incorporate user feedback, and deliver value faster.

In essence, Agile focuses on people over processes, working software over documentation, and responding to change over following a fixed plan — principles outlined in the Agile Manifesto.

Agile methodology is an iterative and flexible approach to product development where teams deliver work in small, incremental cycles called sprints. It emphasizes collaboration, customer feedback, and the ability to adapt quickly to changes. Agile focuses on continuous improvement and delivering value to the customer early and often.

Waterfall model, on the other hand, is a linear and sequential approach where the project moves through fixed stages — requirements, design, implementation, testing, and deployment — with each phase completed before the next begins. It’s rigid and doesn’t easily accommodate changes once development starts.

Key differences:

• Customer involvement: Agile involves continuous feedback; Waterfall involves customers mainly at the start and end.

• Approach: Agile is iterative; Waterfall is sequential.

• Flexibility: Agile welcomes changes at any stage; Waterfall resists changes after planning.

• Delivery: Agile delivers small, usable increments frequently; Waterfall delivers the final product at the end.

The Agile Manifesto, created in 2001 by a group of software practitioners, lays the foundation for Agile methodology. It consists of 4 core values and 12 guiding principles that emphasize collaboration, adaptability, and customer-centric development.

💡 The 4 Core Values

1. Individuals and interactions over processes and tools
   → People and communication are more important than rigid systems.
2. Working software over comprehensive documentation
   → Deliver functional results rather than spending too long on paperwork.
3. Customer collaboration over contract negotiation
   → Engage the customer continuously instead of sticking strictly to agreements.
4. Responding to change over following a plan
   → Flexibility and adaptability take priority over sticking to a fixed roadmap.

🧭 The 12 Principles of Agile

1. Satisfy the customer through early and continuous delivery of valuable software.
2. Welcome changing requirements, even late in development.
3. Deliver working software frequently (weeks rather than months).
4. Business people and developers must work together daily.
5. Build projects around motivated individuals and trust them to get the job done.
6. Face-to-face communication is the most effective way to convey information.
7. Working software is the primary measure of progress.
8. Maintain a sustainable development pace indefinitely.
9. Continuous attention to technical excellence enhances agility.
10. Simplicity—the art of maximizing the amount of work not done—is essential.
11. The best architectures and designs emerge from self-organizing teams.
12. Teams regularly reflect on how to become more effective and adjust accordingly.

In short, the Agile Manifesto promotes people over process, adaptability over rigidity, and continuous value delivery over lengthy, plan-driven development.

Iterative and incremental development is a core concept in Agile that describes how products are built and improved over time.

• Iterative means the team repeatedly revisits and refines the product through multiple cycles (iterations), learning from feedback and improving with each version.
• Incremental means the product is developed piece by piece — each increment adds new functionality or value to the previous version.

Example:

Imagine building a mobile app:

• Increment 1: Core login and signup features
• Increment 2: User profile and settings
• Increment 3: Notifications and personalization

After each iteration, the team reviews feedback, adjusts priorities, and improves the product before starting the next cycle.

In essence, iterative = refining, and incremental = adding value — together, they ensure continuous progress, learning, and customer satisfaction.

Agile is designed to embrace change, not resist it — that’s one of its biggest strengths.

Here’s how Agile helps manage changing requirements effectively:

1. Short sprints: Work is divided into short, time-boxed cycles (1–4 weeks), allowing teams to review progress frequently and adjust priorities quickly.
2. Backlog flexibility: The product backlog is a living list of features that can be reordered anytime based on new insights, user feedback, or market changes.
3. Continuous feedback: Regular sprint reviews and customer demos ensure that the team stays aligned with evolving business needs.
4. Collaborative approach: Constant communication between developers, stakeholders, and customers ensures that changes are discussed and integrated smoothly.
5. Iterative delivery: Since the product is built and released in increments, updates or pivots can be applied without disrupting the entire project.

In short: Agile turns change into an advantage by enabling teams to adapt early, learn continuously, and deliver real value faster.

Agile offers flexibility, faster delivery, and better alignment with customer needs. Its main benefits include:

• Faster time-to-market: Work is delivered in small, usable increments rather than waiting for a full release.
• Continuous feedback: Regular input from users and stakeholders ensures the product stays relevant.
• Adaptability: Teams can quickly respond to changing priorities or market conditions.
• Improved collaboration: Cross-functional teams work closely with open communication.
• Higher quality: Frequent testing and iteration reduce defects and improve performance.
• Customer-centric development: Continuous engagement ensures the product delivers real value.

Example: A PM releases a new checkout feature in small iterations, collects feedback from real users, and refines it over multiple sprints — ensuring high adoption and fewer reworks.

Agile is a philosophy — frameworks define how teams apply it.

Example: A PM might use Scrum for product feature development and Kanban for managing ongoing support requests.

Agile teams track both output and outcome metrics to evaluate progress and impact.

Common Agile metrics include:

• Velocity: The amount of work (story points) completed per sprint — helps forecast future capacity.
• Burndown/Burnup charts: Show progress toward sprint or release goals.
• Cycle time & lead time: Measure how fast work moves from start to finish.
• Customer satisfaction (CSAT/NPS): Reflects end-user value delivered.
• Business outcomes: Metrics like conversion rates, retention, or engagement indicate real product impact.

Example: A PM monitors both velocity (team delivering 30 points per sprint) and NPS improvement after releasing a new user flow to ensure they’re driving value, not just shipping features.

A user story describes a feature from the end user’s perspective, focusing on value rather than functionality.

Format:

“As a [type of user], I want [a goal] so that [I get a benefit].”

Example:

“As a shopper, I want to save my favorite products so that I can buy them later easily.”

Effective user stories are:

• Clear and concise (one user goal per story)
• Testable (with measurable acceptance criteria)
• Valuable (deliver user or business benefit)
• Collaborative (refined with input from team and stakeholders)

INVEST Criteria: Independent | Negotiable | Valuable | Estimable | Small | Testable

Tip: Good stories describe what the user needs — not how the team should implement it.

These terms represent different levels of granularity in Agile planning.

Hierarchy: Epic → Features → User Stories → Tasks

This structure helps PMs manage the roadmap at different levels — from strategic themes down to actionable items in sprints.

Sprints are short, fixed time periods — typically 1 to 4 weeks — during which an Agile team works to complete a specific set of tasks or deliverables from the product backlog. Each sprint ends with a potentially shippable product increment that can be reviewed and improved upon in the next cycle.

Why sprints are important in Agile:

1. Focus and structure: They help teams concentrate on a clear, achievable goal within a defined timeframe.
2. Faster feedback: Frequent reviews ensure early detection of issues and alignment with customer needs.
3. Adaptability: Teams can adjust priorities at the end of each sprint based on feedback and new insights.
4. Continuous improvement: Sprint retrospectives allow teams to reflect and refine their processes regularly.

In essence, sprints drive iteration, transparency, and agility—the core principles of Agile methodology.

At the end of every Sprint, the team inspects the work done, gathers feedback, and plans improvements for the next cycle. The goal is to ensure continuous delivery of value and ongoing learning.

The key activities at the end of a Sprint are:

1. Sprint Review:
   • The team demonstrates the completed product increment to stakeholders.
   • Feedback is gathered to assess whether the Sprint Goal was met and what to prioritize next.
   • The Product Backlog may be updated based on new insights or user feedback.
     → Outcome: Alignment between team and stakeholders on product progress.
2. Sprint Retrospective:
   • The team reflects on the process — what went well, what didn’t, and how to improve.
   • Actionable steps are identified to enhance teamwork, communication, and efficiency in future sprints.
     → Outcome: Continuous improvement in delivery and collaboration.
3. Increment Ready for Release:
   • The “Done” product increment is integrated, tested, and potentially deployable.
   • The PM ensures the increment aligns with product vision and user needs.

📘 In short:

At the end of a Sprint, teams inspect the product and process, get feedback from stakeholders, and prepare for the next iteration — ensuring the product evolves in the right direction.

In principle — no, new work should not be added to a Sprint once it has started.

A Sprint is a time-boxed commitment: the team agrees on a Sprint Goal and a defined set of backlog items (the Sprint Backlog) during Sprint Planning. Changing this mid-sprint disrupts focus, predictability, and team accountability.

However, there are a few exceptions and nuances:

1. Minor adjustments can happen
   If the change helps achieve the Sprint Goal (e.g., replacing a low-priority task with a related one), the team and Product Owner may agree to adjust scope slightly.
2. Major new work — defer to next sprint
   Any large, unplanned request (like a new feature or urgent change) should go into the Product Backlog and be reconsidered during the next Sprint Planning.
3. Urgent, high-impact issues
   If a critical bug or business emergency arises, the Product Owner and team may decide to end the Sprint early or replace some backlog items — but this should be exceptional.

📘 In short:

New work is generally not added mid-sprint. Agile values adaptability, but within a sprint, focus and stability are more important than reacting to every new request.

If the team realizes during the Sprint that they won’t meet the Sprint Goal, the focus should shift from panic to transparency and collaboration. Agile values adaptability — so it’s not about blame, but about learning and managing scope effectively.

Here’s what the team should do:

1. Communicate early and clearly
   • The Development Team should inform the Product Owner as soon as the risk becomes apparent.
   • Transparency allows timely decisions and avoids surprises at the Sprint Review.
     → Example: “We’re behind due to unexpected API issues — we may not complete all user stories.”
2. Reassess priorities with the Product Owner
   • The Product Owner and team collaborate to determine which backlog items are essential to still achieve part or most of the Sprint Goal.
   • Low-priority or non-critical items can be postponed to the next sprint.
3. Focus on delivering a usable increment
   • Even if the full goal can’t be achieved, the team should aim to deliver something valuable and working, not abandon progress mid-way.
   • This maintains stakeholder trust and ensures continuous delivery of value.
4. Identify root causes during Retrospective
   • Discuss what led to the shortfall (underestimation, blockers, scope creep, etc.) and agree on process improvements.
   • Adjust future sprint planning or estimation practices accordingly.

In short:

If the Sprint Goal seems unachievable, the team should raise it early, collaborate with the Product Owner to reprioritize scope, focus on delivering a usable increment, and use the Retrospective to improve future planning.