Work item arrival rate, work item departure rate, work item ageing are key factors to consider for faster service delivery or project delivery.
When we start work as soon as it arrives irrespective of our availability work items age and the number of work items in progress grow resulting in longer lead time which causes dissatisfaction.
Faster Organisation: The quickest way to deliver a work request is to start it when we have availability to work on it usually this means delaying starting it.
Work item ageing and increased work items in progress lead to extra delays in serving the customers resulting in expedite requests that lead to us being reactive and diverting capacity to fulfil the expedite request leading to more work item ageing and more expedite request leading us to be reactive and unpredictable. See the Cumulative Started and Finished graph below.
Cumulative Started and Finished
Plot the started work items and finished one and plot this as a cumulative flow when the rate at which we start the work outstrips our finishing rate the cumulative flow diagram looks like the one below.
Project Management: Manage the work item in progress and work item ageing to achieve a predictable system, the cumulative diagram below shows the system where the number of work items in progress is limited and we are monitoring work item ageing and acting on it. This system is now predictable and we can use our lead time and delivery rates to forcast completion time. It is by building a pull-based system woith work in progress limits that we achieve faster delivery and gain business agility.
Achieve predictable delivery
- Limit work items in progress
- Measure work item ageing
- use cumulative flow diagram to visualise
How predictable is your service delivery?
Accelerate your agility, make the invisible visible, manage the work.