Here's one example: When I started at one recent client, the team was doing "book" Scrum, with two-week iterations and bi-weekly ritual meetings that included retrospective, planning and estimating meetings. These meetings often felt forced and artificial. In the retrospective, for example, the team had to talk, so it brought up either minor issues or repeating, hard-to-address issues.

The iteration boundaries, at one time helpful in creating a sense of urgency, weren't adding much value. Some meetings were straight-up waste. We dropped iterations and moved the meetings to a just-in-time format. This meant sizing each story right before it was worked on, tracking improvement ideas on sticky notes and scheduling a meeting when the list reached six sticky notes.

Since we made that switch, two other teams switched to this continuous flow approach; three other teams continue to use iterations. There was no mandate from management or standard to follow. Certain teams simply saw waste and wanted to eliminate it.

In short, lean thinking means a constant flow of improvement ideas can come from anywhere, at any time, as long as they improve outcomes or reduce risk.