The discussion (of sorts) on Twitter around "no estimates" - what ever that actually means, since there is no definitive description other than exploring - brings me back to my core program management, project management, writing software for money, designing algorithms for identifying moving targets in radar systems, and other software engineering experiences.
Let's start with a fundamental pricniple of all product or service development, either internal or external. While leading a couple hands full of project managers at a large Department of Energy environmental cleanup site, where software development was a critical success factor - and by the way we introduced eXtreme Programming into an ANSI validated Earned Value Management System - our external consulting firm gave us some good advice. We were bidding our technology and services at another DOE site, with similar cleanup problems. We were working on strategies, balanced scorecards, systems architectures, and the like.
That's all nice boys and girls, but here's some fundamental advice - our customer has money and we want it. What's it gonna cost and when will you be done providing the capabilities to close this site?
That's it, that's the winning strategy. The customer has a need, we want to providea solution to it. How much will it cost and when will we have it. If we can answer those three questions - cost, schedule, delivered capabilities, with attached unassailable beneficial outcomes - we will win. This is a business strategy. All the Balanced Scorecard presentations, examples of past performance, deep references of success, are all for naught if the customer can't afford our solution. It comes down to this - and this is where I learned this from the Managing Partner of the Big 6 (at that time) consulting firm.
You can't know the value of something until you know its cost
That's a fundamental principle of all business transactions. Value is always exchanged for cost. We do this when we buy a Venti Nonfat Latte at Star Bucks. We do this when we pay the lawn care company to mow and trim weekly. We do this when we buy anything, including software or the services that produce the software.
This is an immutable principle of commerce
So when we hear, there are alternative ways of writing software for money that don't involves estimating the cost of doing that work, think again. How did you get around the immutable principle of commerce? Now notice I used the word estimate in the same post as know. Yes, estimating allows us to know something to some level of confidence.
I'll estimate that my 1 hour drive to work everyday, will be extended to 1 hour 20 minutes when the snow storm arrives tomorrow night.
I know I'd better have margin in my drive schedule, if I want to attend the 8:30 stand up.
I estimate that it will take 3 days to install and verify the database for the system, given the historical data from the last 3 times we did this.
This knowledge can then be used to plan the access to the server room, arrange for all the verification and validation data we'll need to certify the contents are ready for use by the customer.
We estimate to a degree of confidence, things (time, cost, performance) we'll need to know about to do our job.
So How Can We Learn To Estimate?
Here's where we start. We start with what has taken place in the past. We've never done this before you say. I'd suggest, working literally in the rocket science world, there is very little in the commercial software world that hasn't been done by someone, somewhere in the past. You may not know these people, but it's been done. And more importantly it's the people issues that muck up the project most of the time, not the technical, unless of course it actually is rocket science, or stealth fighter science, or bioscience.
So with the second best basis of estimate approach - What is this like? We've done similar things in the past, how is this problem like those solutions? Next comes the 10 questions approach. The Planning Game. Then a parametric approach. Function Points, COCOMO, SEER, Price-S, SLIM, CoStar, and a long list of other basis of estimate tools, some free can guide you. So when you hear software can't be estimated, change the phrase to I don't know how to estimate software projects, but I can sure look into learning how.
Finally the least desirable way to estimate is to ask the expert. This only works if the expert has been calibrated with a reference class, has her optimism bias in check, knows all about anchoring and adjustment, and has a track record for producing credible estimates. If not, you're going to be disappointed in the result.
But our management uses our estimates against us. Our management doesn't understand the notion of probability and statistics. Our management behaves like Dilbert's boss. This has nothing to do with the need to estimate the cost, schedule, and technical performance of the product and service needed by your customer. It has everyone to do with managing up. And if that's not possible, producing a credible estimate with those risks baked in to protect yourself. And if that's not possible start looking for a better manager or even a better job because your company is going to be in the ditch before long.
So when we hear that estimating is the smell of dysfunction - without ever listing one single dyfunction - remember there are lots of dysfunctions in business. This is normal, because humans are involved. But that dysfunction is not caused by the need to estimate. The need to estimate is a core business process. Doing bad estimates, doing estimates for the wrong reasons, doing estimates wrong - that's a dysfunction that is universal.
In the end you need to either nut up or shut up as Woody says. Yes, that Woody. Learn to estimate for all the right reasons, then when there is an opportunity to have an enlightened manager at your current firm or a new firm, you'll be prepared to contribute value to the business process in ways that benefit the top line.
Since that top line, minus the costs to produce the goods or services is the bottom line (in it's simplest form) is what writing software for money is all about. Knowing the middle line - costs of goods sold (COGS) is critical to actually staying in business.
