Done this. Good question but I don't think it's the most helpful way of thinking about it.

Every new recruit brings their own assumptions about how organizations / employment / etc. work and many of those assumptions won't be visible until after a while. This is especially true for managers.

I found Charles Handy's thinking about four types of organisational culture very helpful and I wish I'd found it earlier in the process.

AI summary: Charles Handy identified four types of organizational cultures: Power Culture, where decision-making is centralized among a few; Role Culture, which is based on defined roles and responsibilities; Task Culture, focused on teamwork to achieve specific goals; and Person Culture, where individual interests take precedence over the organization.

Basically, 15>50 is very likely to involve a shift from one of these to another one and making that open and explicit could help you a lot (including understanding how the role of senior managers needs to change).

The book is Understanding Organisations from 1976 but still valuable.

Good luck!

This might not be the first to break, but it will eventually, and if corrected NOW will make things much smoother:

Your documentation of processes and procedures is NOT adequate.

'everyone used to know about are getting lost' - oh good thing your documentation makes this clear, because it is obviously their fault.

'New hires take forever to ramp up' - oh good thing you have complete ramp up plan and documentation, because it is obviously their fault.

'building on different assumptions' - oh good, your old assumptions are clearly documented, because it is obviously their fault.

So their is your self focus, please do good, and document well.

I think what breaks first is team / org dependent but ime: alignment & quality standards

I found a mixture of shoehorning the vision into as many conversations as possible and occasional in person meetups (we die roughly yearly) helped with vision. I dont have measurements but my concern for teams decision making dropped a lot and disagreements in smaller discussion settings also dropped.

Standards dropping was secretly alignment too but more around why than what. I found building a culture of excellence helped e.g. "we're here to build software we're proud of, from the code to the experience, and you are the right people do it, so lets build something we're proud of.". You or who ever has to actually believe they are the people to so it though.

Im sure people have more concrete and technical examples.

Note the military has a fractal structure such that you still have smaller units inside a bigger operation. I think that’s part of the solution.