The biggest recurring issue I have with my managers over the last twenty years is their need to add unnecessary complexity to projects. I think a good manager stays out of the way and just monitors employees for any obstructions that are preventing them from meeting their goals. Yet, my experience is that when a manager sits in on a project meeting, they can't help but start giving input on the project itself, adding complexity to defined business rules or adding obscure use cases to the system. Too many managers can't help but dominate meetings because their dominant personalities is how they became managers in the first place.
The worst is when you get two or more managers attending the same meeting. Then nothing will get done as they eat up all of the meeting time arguing about business rules, magnifying the complexity of the system until you end up with some Rube Goldberg chain of logic that they will completely forget minutes after they've left the meeting. A good manager knows to trust their employees and only intervenes to make sure those employees have the resources they need to do their jobs. The most effective managers are humble and respect the expertise of the experts they hire.
The best manager I every had was famous for telling his guys to give him the easy 80%, and worry about the hard stuff when someone will pay for it. That person was pure gold, highly effective.
The worst, there have been many. These guys just complicate simple task so no one knows what they're supposed to be doing anymore. Managers should ruthlessly limit scope wherever possible.
Yes, this. Convincing managers to focus on the minimal viable implementation that users can start productively using sooner rather than later and building from there is a real art of senior developers in my experience.
A variation on this theme: years ago I had a manager who was a pretty solid developer who had written a lot of the mission critical code we were supporting. He moved up a couple rungs, got an MBA, brought in scrum (to replace a sclerotic waterfall process), and served as product owner on a lot of our products.
So he was involved in planning meetings and did a pretty good job of steering things there in his product owner role. But once planning was complete and development started, he couldn't resist getting in the ear of individual devs and project managers on the team to alter specs or dictate how he thought things should be implemented. This was after we had met, agreed on a design or strategy (with him present), and started (or even sometimes completed) implementation. It got to the point that we would joke about the stated requirements of a project and the on-the-way-to-the-bathroom requirements.
It really gnawed at both developers and the project managers who worked under him and were responsible for the day-to-day management of the projects. He developed a reputation among the team for being arrogant, aloof, and disrespectful even though that wasn't really his character at all and he was actually a pretty friendly easy-going guy who tried to do things right.
The worst is when you get two or more managers attending the same meeting. Then nothing will get done as they eat up all of the meeting time arguing about business rules, magnifying the complexity of the system until you end up with some Rube Goldberg chain of logic that they will completely forget minutes after they've left the meeting. A good manager knows to trust their employees and only intervenes to make sure those employees have the resources they need to do their jobs. The most effective managers are humble and respect the expertise of the experts they hire.