Waterfall Sucks, Always. Duh.


Today, I had an interesting discussion over Twitter related to project organization in restricted environments. (Update: I’ve removed all references to the actual discussion because the person I interacted with felt mis-quoted, and I don’t think that it was actually that important with regards to what I actually wanted to get across.) This prompted me to take a break from my usual topics and elaborate a bit on my thoughts with more than 140 characters. All this assumes you’re in the role of not only having to actually deliver a piece of software, but also to get the necessary funding – regardless of whether you’re part of an internal organization that requires approval from top management or you’re an external partner that needs to sell to its customer. That said, I’ll focus on the second scenario as that is my primary focus at innoQ.

First of all, in an ideal world, the customer understands all of the reasons that led to the Agile movement, e.g. accepts that an upfront specification that’s 100% correct is an unattainable pipe dream, agrees to participate in the actual development process, and most importantly, understands that what needs to be built will only become clear during the actual development project. We do have some customers who understand this very clearly, and they agree to our favorite pricing model: We offer a sprint/iteration for a fixed price or on a T&M basis, and after each sprint the customer can decide to continue or to stop (which will require one final short wrap-up phase). This reduces the customer’s risk, which is often seen as a benefit big enough to outweigh the perceived disadvantage of not knowing what the overall cost will be. It’s great to be able to work in an environment where everybody’s goals are perfectly aligned, and this is the case in this model.

Unfortunately, this ideal model is not always an option. Of course one way for a development organization to ensure that all projects are done this way is to simply refuse doing it in any other fashion. That’s a good option, but whether it’s actually doable strongly depends on internal power distribution or external market forces.

But what do you do when you have to accept a different set of restrictions? For example, the customer/stakeholder might require a fixed-scope, fixed-time, fixed-price offer. My guess is we can all agree that this is bad idea for everyone involved. But how do you approach things if you just have to do things this way? What do you do if, as an additional downside, the developers assigned to the project are not as skilled as you’d like the to be?

As possible answer might be to use a classical waterfall approach, but I think this is never a good choice. At the very least, go with an iterative approach, even if that means you have to game the system to do that.

Of course you have to put up some effort into an initial up-front analysis. You’ll be aware that much of what you find out may actually turn out to be wrong, but it’s still better to make a slightly more informed estimate up front as opposed to a totally bogus one, especially if you’re an external partner that’s supposed to provide a fixed-price quote. Then, make sure that you grow the system in increments – i.e., build a first working system, using a number of interesting use cases; then add functionality in the next iteration, and continue until done.

Typically, this will resemble something like an agile process – but with slightly larger iterations (e.g. maybe 6 weeks instead of two), and with the added amount of documentation required to fulfill the typical waterfall requirements. (If this reminds you of a Unified Process kind of thing, that’s no coincidence.)

In the end, you’ll have created all of the documents and other artefacts required, but simply not in the order they were supposed to be generated (first analysis, then design, then implementation, then test), but with the trimmed-down focus of each iteration.

Is this perfect? Not even remotely. But in my experience, you have a far greater chance to meet your goals than with actually following the waterfall approach, and even more importantly, management is likely to accept it (partially because it’s obvious, partially because you don’t tell them about it).

If you can’t get away with that, you’re really out of luck, and it’s as they say: You need to change the company, and if you can’t, change companies.