My experience is that senior managers don't have the time or inclination to be aware of operational issues. They are unable to perceive something like there is

My experience is that senior managers don't have the time or inclination to be aware of operational issues. They are unable to perceive something like there is a structural issue between units A and B. These issues are actually seen and surfaced by workers in units A and B, who actually experience the result of the mismatch. If they are able to cross-communicate directly they may be able to resolve the issue without intervention from above. However, they may not be able to, typically if this involves hiring. But the only way that a senior manager could even understand there is an issue is if someone in unit A or unit B makes them aware of it. This is useless overhead. The workers have to be able to successfully communicate the issue up to senior management and usually also suggest the resolution, then get buy-in from senior management on implementation. If instead the workers were more empowered to make decisions themselves the information and decision-making bottleneck could be avoided.