Which is most important? To ensure our teams are fully busy or to maximise the value delivered by the development pipeline? I’m hoping to have you consider that there may be times in when it is in the company’s interest to pay people to “look out of the window” for periods of time.
Throughput decreases as capacity utilisation approaches 100%
Think about a highway – cars flow fine when there is little traffic. When the volume of traffic goes above 80%, we start to get traffic jams. As the loading on the highway approaches 100% then we end up almost no flow at all. The overall value delivered (i.e. people getting to where they want to go) is less. Models have been developed which give the underlying maths of why this is. Highway designers have actually taken these model’s to heart and there are now places were cars are held by traffic lights on the sliproad at peak times in order to maintain a smooth flow on the main highway. The funny thing is this improves everybody’s end-2-end journey time including the cars which were held on the sliproad for a period. Its counter-intuitive, as it probably doesn’t feel like that when you are sitting on the sliproad not going anywhere.
A development pipeline has similar characteristics to a highway. The inherent variation in both demand and supply means that throughput is maximised when the pipeline is run on average below full capacity.
One of the teams I coach is effectively doing a whole release which is dominated by a technical upgrade. To simplify the situation, what that means is that it requires the developers and testers but not the analysts. What should the analysts do whilst the developers/testers are busy with this release?
- Worst option: Do more analysis. Since the bottleneck is not analysis work, all this will do is pile up a lot of work for the developers/testers to work on. This pile will probably never disappear because as soon as the developers remove something from it, the analysts will continue adding a new item. We haven’t increased the value generated by the pipeline but we’ve increased the cycle time and hence decreased agility and speed of feedback/learning. Think of all the management and communication that with be required to look after this pile of half finished work? The overall value generated is almost certainly negative.
- Better option: Analysts look out the window for a while. This has no negative effects on the value delivered. Of course, if this is a permanent thing (which in this case it isn’t) we should look into reducing the number of analysts.
- Best option: Analysts learn over time how to help with development and test. They may not be the most efficient at these tasks. T-shaped individuals can move to the bottleneck and increase it’s capacity. This would enable the technical release to be ready earlier and hence increases the value delivered by the pipeline.
It’s counter-intuitive for us to accept that there are situations where the most value people can generate in the short-term is to do nothing. We all like to be busy. It’s not about the productivity of the individual but the productivity of the pipeline as a whole. What do you think?
A pipeline near you?