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The #NoEstimates Debate: An Unbiased Look At Origins, Arguments, and Leaders
New submitter MikeTechDude writes: Estimates have always been an integral part of the software development process. In recent years, however, developers, including Woody Zuill and Vasco Duarte, have begun to question the efficacy, and even the purpose, of using estimates to predict a project's cost and time line. A fierce debate has sprung up on Twitter, between those calling for an end to estimates and those who continue to champion their use in a professional setting. On the surface, it would appear that the debate is black and white. Proponents of the #NoEstimates Twitter hashtag are promoting a hard stop to all estimates industry-wide, and critics of the movement are insisting on a conservative approach that leaves little room for innovation. However, the reality of the debate has unfolded in far more complex, nuanced shades of gray. HP's Malcolm Isaacs digs deep and pinpoints where the debate started, where it now stands, and what its implications are for the future of software development. Meanwhile, Martin Heller offers his less unbiased approach with his post, #NoEstimates? Not so fast.
Estimates should be used to prioritize features (cost / benefit) as opposed to being used to set hard deadlines.
Estimates should be one of "hours", "days", "weeks", or "months". It is fairly easy for most people to differentiate between features that take hours to implement vs weeks. In my experience, exact durations with multiples for padding have proven to be less useful / accurate than the former method.
Robert Martin recently wrote a book called Clean Coders which discusses exactly how to deal with that problem.
Essentially, he says if you want people to treat you like a professional, then you need to act like a professional. I highly recommend that book, it's good.
Refusing to do estimates is not acting like a professional.
"First they came for the slanderers and i said nothing."
Incidentally, This Manifesto against the agile manifesto entertains me.
"First they came for the slanderers and i said nothing."
Estimates are useless as a measure of how well an engineer is performing. How far he is ahead or behind schedule only indicates the extent to which he was able to get away with padding his estimate in the first place.
That said, estimates ARE very valuable when you have a complex set of interlocking projects and resources that can be tasked in different places. This is especially true if external pressure require that a project be done on an exact date.
To take an extreme example, if the launch window for Europa is at a known date, the spacecraft firmware must be fully tested and installed by that date. Working backwards that says when the first version must be ready. The estimate helps decide what resources should be applied, and later it lets you know if you are so far behind that you need to change the launch date to the next window (over a year away). That affects budget etc.
At SLAC we have complex projects that require the work of lots of people to all come together. This results in very rigid schedules - There is typically a 2 month window for major upgrades, if you miss it, you wait a year. If someone working for me doesn't like doing estimates, I basically say "we need a guess. I can guess or you can, but since you are doing the work, your guess will be better than mine".
I have worked in the industry for 20+ years and here are my observations - granted, I have worked in smaller companies (i.e 25-4000) and startups.
Estimates work as a means to determine the work effort for a given set of features. They are not to be used for setting schedules and deadlines by themselves. They are to be used for budgeting and cost planning. And, they are not to be done without a detailed design meeting the agreed upon requirements.
Unless your client is very rich and/or stupid or you have a large surplus of venture capital in your startup, you better be concerned with the work effort and time to have your product in a usable state. When you can tell a client that a project is going to take time X and cost Y and meet those values, you gain credibility and trust. In the digital advertising world, those with credibility and trust become the agency of record (AOR). And, the client will stick with you as their AOR until you royally screw up and fail to deliver what was promised, when promised and for the agreed upon price.
You DON'T ask a developer how long something will take - they invariably will underestimate the work effort. Instead, at least until you have measured delivery rates for your team members, you use industry standards. You can ask the developer and then compare their estimates with the actual time and effort. When their estimates start matching up, you can ask them estimate their own assigned work. It can be a good learning experience for them.
Some projects don't require estimates. We had projects that fit a template model based earlier work. We knew how long it took, on average, to fill the various fields of the template. Throw in the project management, QA and deployment components and its pretty easy to do.
When people claim Agile isn't compatible with estimates, it's probably because the team isn't concerned about documentation or planning. They tell you that the system has too many variables and they don't have time or resources to keep the design up to date. I call BS. If you can't do it, then add someone to the team who can. There are great tools for doing design work and capturing requirements at all phases of a project - use them.
Even with Agile, you should layout out a basic design or framework in the early stages of the project. Then, you can determine how long other features will take and what their dependencies are before you attempt to implement them and emptying the client's wallet. Then, you base the number of sprints based on that information. Since you are supposed to have a working product at the end of each sprint, you should be able to tell the client what features will be in each deliverable and cost. If they want to change the requirements or add new features or change functionality, you still have to plan how long those features will take and in which sprint you will deliver a product that meets those changes.