Defect Lifecycle: A Real-World Example and Detailed Insights!

 The Defect Lifecycle is the journey a defect takes from identification to closure in the software development lifecycle. It outlines the various stages a defect goes through and helps in tracking, managing, and resolving defects efficiently.

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Stages of Defect Lifecycle

1. New:
   When a tester identifies a defect, it is logged into a defect-tracking tool (e.g., Jira, Bugzilla) with all relevant details (description, steps to reproduce, severity, screenshots, etc.).

   Example: A tester notices that entering invalid credentials on a login page doesn't display the correct error message. They log the defect in Jira with the following details:

   • Title: Incorrect error message for invalid login.
   • Steps to Reproduce: Enter invalid credentials and click "Login."
   • Expected Result: "Invalid username or password" should appear.
   • Actual Result: "System error" appears.

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2. Assigned:
   The defect is reviewed by the lead or project manager and assigned to a developer based on the module or expertise.

   Example: The lead assigns the defect to the backend developer responsible for the login functionality.

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3. Open:
   The developer begins analyzing the defect to identify the root cause.

   Example: The developer investigates and finds that the API responsible for error handling is returning a generic response instead of specific error codes.

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4. Fixed:
   Once the issue is resolved, the developer marks the defect as “Fixed” and updates the comments with the changes made.

   Example: The developer updates the API to return proper error messages and ensures the front-end displays them accurately. They then commit the changes to the code repository.

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5. Retest:
   The tester retests the defect to verify the fix using the steps to reproduce.

   Example: The tester verifies that entering invalid credentials now shows "Invalid username or password" as expected.

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6. Verified:
   If the defect is resolved as expected, the tester marks it as “Verified.”

   Example: After multiple tests, the tester confirms that the error message is displayed correctly across browsers and devices.

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7. Closed:
   If no further issues are found, the defect is marked as “Closed.”

   Example: The lead reviews the resolution, and the defect is officially marked as “Closed” in Jira.

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8. Reopen (if applicable):
   If the issue is found to persist during retesting or UAT, the defect is reopened and re-assigned for further investigation.

   Example: During UAT, the client finds that the error message isn't localized for certain regions. The defect is reopened for localization fixes.

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Defect Lifecycle Flow Diagram

Here’s a simplified flow of the lifecycle:
New → Assigned → Open → Fixed → Retest → Verified → Closed
If required: Reopened → Assigned → Open → Fixed

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Importance of Defect Lifecycle

• Ensures transparency: Everyone involved can track the progress of a defect.
• Improves quality: Proper management ensures all defects are resolved effectively.
• Boosts collaboration: Facilitates communication between testers, developers, and stakeholders.