When an organization has a lot of decision-makers, the execution is slow. For instance, in family-run businesses where the parents and siblings are all involved in the business, the clash of ideas, vision, and management style, all lead to slow execution. You have to find common ground and this is hard.
Compared to one-person founders where only one person makes the decision, execution is quick.
Most big corporations despite their scale and money fail to innovate like startups because there are plenty of middle-managers who get in the way of decision-making. That is probably why it is better for these giants to acquire startups rather than innovating and executing themselves.
There should be only a very few decision makers so that execution is fast.