Lean, Lean in Hospitals, Lean in Software Development, Lean Management, Theory of Constraints and a lot of other names for one simple idea: Focus. Ken and Jeff mentioned 1999 in “Agile Software Development with Scrum” that Scrum is based on a key values: “Focus.”
In “The Flow“, Mihaly Csikszentmihaly shows that Happiness will be achieved when people can work focused on special assignments, when they believe they are on a mission, when the work they do is challenging and still achievable.
Clear goals (expectations and rules are discernible and goals are attainable and align appropriately with one’s skill set and abilities) – Wikipedia
He called the status that a person reaches when he is fully engaged and happy “Flow.”
So what Mihaly Csikszentmihaly basically says is that we need to have „focus“ to reach happiness and our full engagement.
Does this mean you are working on one TASK at the time? No!
It means we, as a Scrum-Team, are working towards one goal, one thing we want to achieve. A lot of us do misunderstand focus with working on one thing only. “Working on one thing only” is a tool. It helps you to learn that focus will bring faster and therefore more results. One-Thing-At-A-Time means for the individual he or she shall work on one task that is about 2 or 3 hours long. In a concentrated way without distraction. That can also mean you work with a partner on this piece. And in a team environment we create a common focus by working backlog item by backlog item, every person does its special task.
Focus needs concentration and an emotional attachment to the work you do.