One of the most counterintuitive insights Reinertsen offers is about utilization. Conventional wisdom pushes for 100% resource utilization to keep people "busy." However, Reinertsen demonstrates mathematically that in any system with variability (which all product development has), high utilization creates long queues. He shows that queue time dominates cycle time in product development; a typical feature might have 40 hours of work time but 400 hours of waiting time in various queues.
Small batch sizes reduce holding costs (the cost of keeping unfinished work) but can increase transaction costs (the cost of setting up, testing, and deploying).
Since its release, "The Principles of Product Development Flow" has garnered widespread acclaim, described by numerous sources as “quite simply the most advanced product development book you can buy,” and has been recognized with several awards. One of the most counterintuitive insights Reinertsen offers
Look at your current board. Cut the allowed work-in-progress items per person or per column by half. Focus team energy on unblocking stuck items.
Institutionalizing slow, risky processes. Small batch sizes reduce holding costs (the cost
If you want to dive deeper into optimizing your operational pipelines, I can provide practical templates to help you get started. Let me know if you would like to:
Product development flow is a holistic approach to product development that focuses on creating a smooth and continuous flow of work from idea to delivery. It is based on the principles of lean manufacturing and agile development, and aims to eliminate waste, reduce variability, and improve overall efficiency. Cut the allowed work-in-progress items per person or
The shift from "doing agile" to "being flow-based" is the single largest competitive advantage available in 2025. The tools (Jira, Asana, Trello) do not matter. The economics matter.
Reinertsen’s logic is simple: smaller batch sizes reduce cycle time and risk. By breaking work down into smaller, more frequent releases, organizations can get feedback faster, learn more quickly, and adapt to changes with minimal disruption. This principle directly supports the practices of continuous delivery and agile methodologies, providing a rigorous economic justification for them.
Henry Ford made manufacturing efficient. Toyota made logistics efficient. Donald Reinertsen made thinking efficient.
What your product falls into (e.g., SaaS, physical hardware, medical devices)? The current size of your development organization?
