10 Reasons Estimation and Planning Fails and What to Do About It by Troy Magennis

Great pitch.

Love the basics here, such as:

• “If you are in the non-linear region of utilization for your project (i.e. greater than 80% utilization) then estimation will always fail”,
• “Sometimes you need just enough information to decide what not to do, and perhaps toss a coin for remaining options (if they really are close enough)”,
• “why this project won't finish on time is because of last project - and no amount of estimating is going to help”

And the importance of understanding dependencies (see Why Should We Work Harder to Eliminate the Effect of Dependencies? for more on this thinking.

The base idea is that a lot of bad things happen which increase utilization into the “non-linear” zone and which make estimating useless and forecasting difficult.