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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.
No, hashtags are not movements. If you think so, you either have no clue what a movement is or no clue what a hashtag is, and I'm guessing it's the former. Talking about things on Twitter is talking and that's it. It's not some kind of political action.
Not so. The second one has a correct and professional answer: "I do not know. This will require a pre-study. But adding new requirements during the process is right out, then the pre-study has to be repeated and the project reset." and on the pre-study you _can_ deliver a reasonable estimate.
It is not only bosses demanding infeasible things. It is also coders not enlightening them on what is possible and what is not.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
is giving estimates without a detailed design.
Imagine this interaction:
Customer: I want you to build me a house.
Contractor: Ok, How many square feet?
Customer: I don't know. When can you start?
Contractor: We can't start until we have plans drawn up.
Customer: I don't have time for that. How much will it cost?
Contractor: I can give you a rough idea once we've nailed down the square footage, number of stories, type of foundation, and some other details.
Customer: You are wasting my time with all these questions.
Contractor: Go Away.
Yet software developers agree to this situation, or are forced to agree to it, all the time.
more cowbell
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.
I'll admit that I'm not a developer, so I may not have a firm grasp on the relevance of everything being talked about. However, I've managed my share of projects, and I definitely think there's reason to doubt the value of estimates for all kinds of projects. Software development projects are not unique in that regard.
Now, I want to start by pointing out the obvious that you often have to make some kind of estimate. Even if the estimate isn't very precise, you have to make some kind of guess-- is this going to take 1 day, 6 months, or 5 years? Being practical, people have to have some idea of what they're getting into, or they can't make decisions.
On the other hand, estimate can only be accurate insofar as the scope of the project is well defined and well understood. For tasks that you do frequently and know exactly what needs to happen, accurate estimates are not very difficult. Even if you are bad at estimating, you can measure how much time and money is spent on those repetitive tasks, and then use that data to figure out how much time and money it typically takes. However, as the scope of work is less well defined, or the nature of the work is less well known, the accuracy of the estimate will be worse.
Imagine building a house. If you're building 100 houses in a development, and you do that work often, and you've already build 30 houses and know how much the labor and materials cost, then you can probably make a good guess of how much time and money it will take to build the remaining 70. However, if someone asks you to "fix all the problems with their house," and you don't know what shape their house is in, what it means to "fix" it, what the laws are regarding construction in the area, or what the local materials/labor cost, then your estimate won't be worth much.
And this brings me back to the issue of "precision" rather than "accuracy". I think part of the issue is to provide an appropriate expectation of precision when providing estimates. I frequently have to provide estimates, and some of them are wildly wrong, but when I'm not confident in the estimate I'm providing, I'll also provide some kind of disclaimer. I admit that I don't know all the details about the situation I'm getting into, and that my estimate could be off. The thing that I'm saying will take 6 weeks might take 2 months. Maybe 2.5 months. Maybe more. Not 6 months-- at least not unless there's something really unexpected or some kind of mission-creep.
But this is really part of a larger problem: the ineffectual nature of "plans". There's a famous quote, something along the lines of, "no battle plan survives the first contact with the enemy". Again, there are projects where the scope is defined and the work to be done is well understood, and in those cases, you can do conventional project planning. You can set milestone dates and make gantt charts, and develop a whole timeline and budget. But on the other hand, Donald Rumsfeld was on to something when he talked about "unknown unknowns". Often when you are embarking on a project, you're not even aware of the obstacles you're going to face, and so you can't account for them. This doesn't mean there's no point in developing a plan or a schedule. It means that your schedule has to be flexible in proportion to the likelihood of "unknown unknowns" and other contingencies outside of your control.
I think if you want to improve the situation, the answer isn't to stop making estimates or project plans, but to develop better methods for quickly estimating the precision of your estimates, providing a margin of error, or the level of flexibility needed in a project. However, I think the #NoEstimates people are correct to point out that there is often diminishing returns on trying to set deadlines and budgets. It doesn't make sense to spend a week refining your plans for a two-week project.
If you can't produce a reasonably accurate estimate you may not have asked the right question.
How long will it take you to do this thing that nobody has ever done before
This is not the right question. The right question is: how long will it take you to assess this thing that nobody has ever done before, and devise strategies for doing it, and develop them to a point that you can estimate how long executing these strategies will take.
Nothing wrong with saying, "I need four weeks to research this before I'll be able to give a reliable estimate on implementation."
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
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.