I got a bit confused about how functional organisations are thought to be more efficient than matrix organisations. Yes, functional organisations might have in-depth expertise (specialisation) but dont matrix organisations reduce duplication of work, as the energy of the team is divided on an as-need basis thus making them more efficient? Doesnt the latter give the advantage that you can have subject matter experts from each function, and bringing them together into a matrix structure only propels the organisation to more efficiently achieving results?

I think saying that one type of org structure is more efficient than another will again be relative to what the organisation is trying to achieve, which then leads me to also disagree with Kaplan & Norton in saying that org structure can be abandoned and systemic measures should just be placed to achieve high performance. Im a strong believer in the saying what gets measured, gets done and I think the balanced scorecard is a good way to do it, but its not limited to that. As the firm becomes more diversified with each business unit having different goals, types of customers, and even nature of the product/service from one another, the structure (and culture) all the more become important to enable peak performance.

As to why Google restructured to Alphabet? Staring at slide 17, my knee-jerk reaction was that it was a part of their clean-up drive to properly separate business units according to their products/services and business model. Then I thought it might also be for the entire organisation and their investors to have clearer delineations on each sub-organisation as they have a more diverse business (playing in other industries like robotics, transportation and even life sciences). Separating business units according to what it delivers, I think, gives a better gauge of how a particular business is really doing, promoting better transparency to its stakeholders (investors included). It's also an easier way to map their competitors, and acquire others if they want to grow a particular BU, or divest it if it's no longer aligned to the conglomerate's overall strategy.

And yes, my previous companys org structure is crazy complicated. Id say it has its pros and cons but with slightly more cons on the stress management of employees that are reporting to 2 GMs with different priorities.

My thoughts probably need distillation. Happy to be corrected in how I am thinking about the relationship between efficiency & organisational structure, and why Google restructured.