This is a good argument for continuous release and agile over waterfall. When making estimates, I also like to differentiate between what I call happy-path pro

This is a good argument for continuous release and agile over waterfall. When making estimates, I also like to differentiate between what I call happy-path projections and lazy-bayesian estimates. The former take a sort of get-there-from-here best-case-scenario approach with some buffer tossed in to make it seem like we're not completely delusional. Lazy-bayesian estimates try to identify similar projects or references as a baseline for forecasting. Daniel Kahnemann refers to the two approaches as the inside and outside view in Thinking Fast and Slow and offers an excellent tale to illustrate the difference: http://txti.es/kahneman-outside-view http://txti.es/kahneman-outside-view I wish I could get every project manager I work with to read this. (I've tried.)