Take the estimate, then do the real maths.
You'd think coding is close to an exact science, at least that's how it looks in movies. So why is it so difficult to estimate when a feature or product will be ready?
Estimates fail for two fundamental reasons. Optimism and incomplete data. Everyone assumes developers are the best versions of themselves and can totally nail new challenges. We plan as if they'll work with perfect designs, clear requirements, and stable priorities. But optimism about developer performance is the foundation of every blown timeline.
Stop believing the optimism, right now. Be pragmatic. Prepare for obstacles, and everything that turns out to be a smooth ride becomes a bonus. This mindset is easy to advocate but hard to maintain. Once you know a team's capabilities and ship a few successful milestones, confidence becomes seductive. Even experienced PMs fall into the trap of planning for potential rather than what's probable. We never learn from this pattern because hope consistently overrides experience. "This time will be different" seems to be vestigial, probably a throwback to a time when Neanderthals were convinced that the next mammoth hunt would definitely go according to plan.
Understanding why estimates fail is more valuable than pretending there's a universal trick to fix them. This chapter dissects the specific traps that turn "simple features" into sagas, so you can plan for reality instead of hope.
A rule of thumb for handling estimates - The specific multipliers I use when developers give me numbers
Team-based estimation - When estimate planning works vs. when it's just a ceremony, and what to do when the numbers are wrong
The confident one-liner - Why "it's just a quick fix" is a dangerous phrase in product management
Process vs. reality - Plan for work as it actually happens, not how the framework says it should
The Product Manual gives you the complete survival guide across every PM challenge: building a plan, stakeholder management, saying no, working with developers, validation, launches, and all the messy reality between theory and practice.
360 pages. No fluff. Just what actually works when you're in the trenches.
Written for PMs with 0-3 years of experience who need answers that work in the real world.