I was at Yahoo under Marissa Mayer, who instated a weekly Friday all-hands, FYI, obviously modeled on whatever Google had. Those who worked at Yahoo before her said that it was a huge change, because previous upper management was pretty much invisible, no-one knew who they were, what they did, what they were thinking, which direction the company was going in.

So even if you're 100% cynical about it and thinking the all-hands are just internal PR, it was still a positive change, because you got to see upper management, see them talk about where the company was going and why, and they had to "defend" their direction.

Of course, the flipside to this is that if it seems like upper management doesn't have their shit together, meetings like these make that obvious, which can torpedo morale.

TGIF used to have a number of highly technical and informative main presentations. There was a great one by the self-driving cars team where they showed some of their tools and explained some of their challenges (great anecdote about why one iteration of the cars was afraid of fixie bicycles). And it wasn't just software - Patrick Pichette did really informative breakdowns of the quarterly earnings results, and the legal team sometimes went into surprising depth on major cases.

These were rarely directly useful, but the practice reinforced a sense of curiosity and mutual respect.

I think so. To put in Taleb's turns, they are very "anti-fragile". They allow a company to benefit from randomness.

Satya started them at Microsoft (monthly though, IIRC), and I personally loved them and derived a lot of value from them about what was going on company wide and perhaps learning new places I might be able to contribute. It also just made me trust leadership more and more motivated to work there. Was only an ~hour a month and I'm sure led to many unpredicted positive effects.

Weekly seems a bit redundant to me, but at minimum a quartetly meeting helps people understand how what they do corresponds to the bigger picture, as well as how well the big picture is actually going.

Also, by letting employees know that their work ties into the bigger picture, you help encourage a bit more innovation at the lower level / on the ground, so to speak.

I've been at companies that did it well, very poorly, not at all, and everywhere in between... So yeah, sometimes really useful, other times the meeting itself can feel like make-work.

They were incredible back when they were private. Unprecedented level of transparency for a company of that size.

Good question. I have had all-hands in the past that were used to hear the intended direction of how goals were going to be measured, which was useful since there is always some whisper-down-the-lane noise for the actual message. But I have also been a part of all-hands that were just PR fluff about what a great job everyone is doing. So, I guess as most things, it depends.

Are any meetings ever useful to anyone?

Rarely. Most could be summarized in email.