Let me put it differently and talk about immediate managers only. If the people problem is coming from other teams, the immediate manager should "shield" their

Let me put it differently and talk about immediate managers only. If the people problem is coming from other teams, the immediate manager should "shield" their team members from that. If it is between their team members, then they need to somehow manage the person reporting to them. They can't always, and I personally find that understandable. But still, the "people leave managers" expression is implying that either that manager is not capable or they are not being given enough resources, authority or training to manage people in their team and outside their team. From the CEO down to line managers, management is responsible for setting the tone and culture. Jeff Bezos and Tim Cook alike are responsible for how horrible and toxic of a work environment exists at amazon and apple. If the company is great, employees can usually switch teams when they don't like a manager.