In this entertaining article, the author recounts a personal misadventure with installing a washing machine in a brand-new house—a task he originally estimated would take a quick 10 minutes but ended up consuming four exhausting hours. His journey, full of unexpected blockers like missing drill holes, incompatible tools, misleading parts, and even a drainage issue that required drilling a PVC wall, becomes a vivid metaphor for the unpredictable nature of software effort estimation. Just as in software projects, where "unknown unknowns" can derail the best-laid plans, his experience underscores that even familiar tasks can hide unforeseen challenges that completely upend initial time estimates.

Key Points:

• Overly Optimistic Estimates: The author confidently assumed a 10-minute installation based on previous experience but ended up spending four hours due to unforeseen challenges.
• Unexpected Obstacles: Each step presented a new blocker—ranging from the need for a specialized 60mm hole saw and a powerful trade drill, to misleading hose designs that didn't expand as expected.
• Practical Lessons Learned: The saga highlights the importance of anticipating “unknown unknowns,” a phrase he uses to describe those unexpected issues that can turn routine projects into major time sinks.
• Analogy to Software Development: The experience is used as a metaphor for software effort estimation, where even small overlooked changes—like new requirements or outdated tools—can dramatically alter the project’s timeline.
• Multiple Trips to the Hardware Store: His journey required five distinct trips to purchase or borrow new tools, mirroring how additional, unforeseen tasks can accumulate in any project.
• Takeaway Message: Just as an apparently simple washing machine installation turned into a protracted ordeal, software projects that appear similar on the surface might require more time due to critical, overlooked differences.
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