Yep. Developer managers tend to pull the team with their development ability (because they have presumably been good at it before they got promoted) at the cost

Yep. Developer managers tend to pull the team with their development ability (because they have presumably been good at it before they got promoted) at the cost of management practice and focus on the team. This means you are in a fundamentally different team. I have seen it is hard for developers to shed their development skin and become real managers. They might feel they need to prove their ability by being able to make all these decisions or even code themselves. There is probably couple of other things happening. But that also means the team has less development responsibilities because manager will make all most important development decisions. And people who do not have important responsibilities tend to devolve. Now, the world "tend" is everywhere here and it just represents the fact that every manager is different. I just mean this as a general observation from 20 years of working in development in companies like Canal+, HP, Intel, Samsung, Credit Agricole, Credit Suisse, Citi and others. There were better and worse managers and there were definitely some good managers who were developers before.