Scaling up a company without losing the culture that originally made it great is incredibly hard. If you're below 150 employees, it's still possible to function using instinctive tribal mechanisms: Dunbar's Number is a big deal when it comes to effective organisational design.
Once you get beyond that, though, you need a plan to avoid descending into the toxic nature of the typical modern enterprise, which is the last bastion of feudal authority. We rejected feudalism as a model for running our societies, why should we accept it as a suitable model for running a business?