Gandhi (at least as reported by his grandson Arun) once said, "We need to be the change we wish to see in the world." This is equally applicable to the world of work—an agile adoption needs agile adoptees. Scrum and lean development cannot be successfully adopted with command-and-control management, predictive planning, or process recipes or "best practices" coming from ivory towers.
Even when those involved in an agile adoption have a conducive mindset, a repeating problem we have seen is a lack of Go See behavior, and therefore, a lack of insight into the real problems and useful solutions. How many product leaders or process engineers spend time regularly sitting with developers while doing the real hands-on work? Without that experience, initiatives have little useful impact; they can also focus in the wrong area—on management-level 'improvements' rather than at gemba.
Scrum, lean, agile development: these are never finished being adopted. Agile is not a change project. Rather, continuous improvement is a pillar of lean thinking, coupled to the idea that the people best suited to create improvement experiments are the workers.
Naturally, hands-on workers at gemba also have limitations. All people—including us—get stuck in inside-the-box behaviors and beliefs that inhibit challenging the status quo. So, in a lean enterprise, manager-teachers who deeply understand lean thinking, who have constancy of purpose, and who inspire kaizen mindset in others are a key positive force to promote and sustain a culture of agility.
But meaningful change and improvement cannot rely on manager-teachers; it relies on...us.