[beat]

Another bit of wisdom I got from Kent Beck is that there are three basic controls to every project... schedule, scope, and resources. You can only control two of them. And resources are generally fixed at the beginning of the project(1), so most projects are either scope-bound (we must have all these features), or schedule-bound (we must hit this hard date). If you're feature-bound, estimation failure means you'll be late. If you're schedule-bound, estimation failure means you'll be incomplete.

This can be a very hard pill for the business to swallow. They want it all, and they want a predictable schedule. But Beck's triangle is akin to thermodynamics. Do you want the volume, or the pressure, or the temperature? When fixing devops-related and agile-related process problems, I often hear "But we're a schedule-driven company!" when they have a scope-driven problem like process transformation.

1. As The Mythical Man-Month pointed out almost 50 years ago, adding resources to a late project makes it even later.

[house9-2]

> If you're schedule-bound, estimation failure means you'll be incomplete.

Schedule-Bound development (or Deadline Driven Development) can actually work well with minimal estimation as long as you are truly building MVP (minimum viable product), you have to ruthlessly slash features and only build the core features that are going to deliver the most bang for the buck.

Not easily done.

[Drdrdrq]

There is a fourth control of course which comes into play when nothing else will give room: quality. You can take many shortcuts to deliver in time, full scope, with the resources available. But the result will be buggy and/or unmaintainable.

Surprising amount of companies choose this path, I guess most without realizing it.

[pas]

Quality is basically inherent in scope. Is testing the product in scope? Yes, then it will take up precious resources (time). Do you want to test it on every platform? Yes, even more time. (And of course the same goes for code review, writing unit tests, planning, writing and discussing a design document, etc.)