One of them is: technical ability is actively detrimental to your power and career. You have to spend time and energy on actually doing things, and every competent manager will do their best to keep you right where you are, with as little political influence as possible.
Conversely, as a manager, so the book says, you want to avoid actually doing anything. You should start initiatives -as many as you can- and deftly use your political capital to either own, disown, or weaponize them. Whether they succeed in creating value is irrelevant, certainly not something you should focus on.
People focused on success and value of initiatives are still working hard when you have moved on. These people are hopelessly behind the scheming manager, eating crumbs.
And if necessary, you the manager just claim credit retroactively.