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Laws in Software Development: 80/20 Rule in E2E Test Automation

Laws in Software Development: 80/20 Rule in E2E Test Automation

“Achieving More with Less”

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Zhimin Zhan
Aug 02, 2024
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The Agile Way
The Agile Way
Laws in Software Development: 80/20 Rule in E2E Test Automation
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This article is one of the “Laws in Software Development” series:

  • 80/20 Rule

  • Broken Window Theory

  • Parkinson’s Law: “work expands so as to fill the time available for its completion”

  • Sturgeon’s law: “ninety percent of everything is crap”

  • Murphy’s law: “Anything that can go wrong will go wrong”

  • The 10,000-Hour Rule: “The key to achieving true expertise is simply a matter of practicing”

  • Brooks’ Law: “Adding manpower to a late project makes it later.”

  • Hosftadter’s Law: “It always takes longer than you expect, even when you take into account Hofstadter’s Law.”

  • Conway’s Law: “Any piece of software reflects the organizational structure that produced it.”

  • …

Table of Contents:
· The 80/20 Principle
· 20% Automated E2E (UI) Tests Cover about 80% of Code Base
· Regression Testing: 80% Automated E2E (UI) and 20% Manual (Exploratory)
· 80% of E2E Test Automation Effort on Test Stabilization and Maintenance

The 80/20 Principle

Many people know “The 80/20 Principle: The Secret to Achieving More with Less” from Richard Koch's best-selling book of the same name.

The 80/20 principle is all around us:

  • 80% of sales come from 20% of clients.

  • One-fifth of your time (equivalent to one day a week) produces 80% of your important work.

  • 80% of crimes are committed by 20% of criminals.

  • 80% of a company’s output is produced by 20% of its workers.

This page lists another 100 examples of the 80/20 principle.

Of course, 80% or 20% is just an indicative figure, so don’t get fixated on that exact number.

In this article, I will list three examples (that I observed) of the 80/20 principle in software testing and development.

20% Automated E2E (UI) Tests Cover about 80% of Code Base

In planning E2E Test Automation, there are commonly two extreme views:

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