I'm going to add on to this: aside from every competitor having to build their own product from scratch, a vertical structure of leadership allows for an individual or small group to have massive resources invested into their ideas. Which are so very often deeply flawed ideas.

Have you looked at Paint3D? Microsoft had a vision for a future where we interact with 3D objects in daily life and we would need a basic software to edit them, just like we use Paint to edit the images that we interact with. It's kind of insane, i can't even guess how many man-hours were spent on it by Microsoft developers.

And absolutely nobody has ever used it.

You can find more extreme examples, especially if you look outside of software (oh god the military); but Paint3D is one of the more accessible ones, any Windows user can check it out right now.