There's an inherent gap between managers and programmers, which does indeed makes programmers the best managers. As a manager, you don't know what does "better

There's an inherent gap between managers and programmers, which does indeed makes programmers the best managers. As a manager, you don't know what does "better architecture" mean. You don't know which practices of your favorite methodology are bullshit. You're always left guessing. Unlike business, programming has a steep learning curve. Managers cannot understand programming, but programmers can understand business needs. At the same time, people who become programmers, typically lack skills required for managers. They also lack interest into those skills. So most programmers turned managers are a complete disaster. Basically programmer-managers have greater variability: some of them are the best, but most are the worst. Promoting programmer to a manager is a high-risk high-reward gamble. The distribution is inverted bell curve, so examples/counter-examples are pointless, they are just anecdotes.