Wednesday 23 November 2011

I Know the Cost but Not the Value

[I wrote the vast majority of this post “the morning after the night before”. I hope that 9 months later I’ve managed to finish it in a more coherent manner than I started it…]

Back in February I made a rare appearance at the eXtreme Tuesday Club and got to talk to some of the movers and shakers in the Agile world. Professionally speaking I’ve mostly been on the outside of the shop looking in through the window wondering what all the commotion is inside. By attending XTC I have been hoping to try and piece together what I’ve seen and read about the whole “movement” and how that it works in practice. As I documented in an earlier post “Refactoring – Do You Tell Your Boss?” I’ve long been struggling with the notion of Technical Debt and how I can help it get sold correctly to those who get to decide when we draw on it and when it’s paid back.

That night, after probably a few too many Staropramen, I finally got to enter into a discussion with Chris Matts on the subject and what I can’t decide is whether we were actually in agreement or, more likely, that I didn’t manage to explain correctly what I believe my relationship is with regards to identifying Cost and Value; in short, I can the former (Cost), but not the latter (Value). So maybe my understanding of what cost and value are is wrong and that’s why I didn’t quite get what he was saying (although I can’t discount the effects of the alcohol either). This post is therefore an opportunity for me to put out what I (and I’m sure some of my colleagues agree) perceive to be our place in the pecking order and the way this seems to work. I guess I’m hoping this will either provide food for thought, a safe place for other misguided individuals or a forum in which those in the know can educate the rest of us journeymen...

From the Trenches

The following example is based on a real problem, and at the time I tried to focus on what I perceived to be the value in the fixes so that the costs could be presented in a fair way and therefore an informed[*] choice would then be made.

The problem arose because the semantics of the data from an upstream system changed such that we were not processing as much data as we should. The problem was not immediately identified because the system was relatively new and so many upstream changes had been experienced that it wasn’t until the dust started to settle that the smaller issues were investigated fully.

The right thing to do would be to fix the root problem and lean on the test infrastructure to ensure no regressions occurred in the process. As always time was perceived to be a factor (along with a sprinkling of politics) and so a solution that involved virtually no existing code changes was also proposed (aka a workaround). From a functional point of view they both provide the same outcome, but the latter would clearly incur debt that would need to be repaid at some point in the future.

Cost vs Value

It’s conceivable that the latter could be pushed into production sooner because there is notionally less chance of another break occurring. In terms of development time there wasn’t much to choose between them and so the raw costs were pretty similar, but in my mind there was a significant difference in value.

Fixing the actual problem clearly has direct value to the business, but what is the difference in value between it being fixed tomorrow, whilst incurring a small amount of debt, and it being fixed in 3 days time with no additional debt? That is not something I can answer. I can explain that taking on the debt increases the risk of potential disruption to subsequent deliveries but only they are in a position to quantify what a slippage in schedule would cost to them.

Perhaps I’m expected to be an expert in both the technology and the business? Good luck with that. It feels to me that I provide more value to my customer by trying to excel at being a developer so that I can provide more accurate estimates, which are very tangible, than trying to understand the business too in the hope of aiding them to quantify the more woolly notion of value. But that’s just the age old argument of Generalists vs Specialists isn’t it? Or maybe that’s the point I’m missing - that the act of trying to quantify the value has value in itself? If so, am I still the right person to be involved in doing that?

I’m clearly just starting out on the agile journey and have so much more to read, mull over and discuss. This week saw XP Day which would have been the perfect opportunity to further my understanding but I guess I’ll have to settle for smaller bites at the eXtreme Tuesday Club instead - if I could only just remember to go!


The workaround cited in the example above is finally going to be removed some 10 months later because it is hopelessly incompatible with another change going in. Although I can’t think of a single production issue caused by the mental disconnect this workaround created, I do know of a few important test runs the business explicitly requested that were spoilt because the workaround was never correctly invoked and so the test results were useless. Each one of these runs took a day to set up and execute and so the costs to the development team has definitely been higher. I wonder how the business costs have balanced out?


[*] Just writing the word “informed” makes me smile. In the world of security there is the Dancing Pigs problem which highlights human nature and our desire for “shiny things”. Why should I expect my customer to ever choose “have it done well” over “have it done tomorrow” when there are Dancing Pigs constantly on offer?

1 comment:

  1. I think all you can do in these situations is build trust by setting out your reasons for recommending action (a) over action (b) in writing to those who "feel informed enough to make the decision".

    They'll select the "wrong" option most of the time, at least to start with. But if you keep at it and clearly explain why each previous choice failure resulted in particular business issues then they may start to come around to selecting the "right" options.

    This takes time. I went through this working at an IBank in London a while back (see and slowly managed to move the business from a situation where we had no release process and people simply hacked fixes into production to one where we had a reliable release system with a regular release schedule which we kept to most of the time but the business knew they could insist on an emergency release if they really needed it.

    The key point was slowly gaining the trust of the business people and explaining the actual cost of all the "shiny things" that the previous developers had been giving them...