A manager can be sitting with a pile of projects and items on his or her 'to do' list and a personal problem arrives.
Most managers know that items on the project and 'to do' lists on his desk will disappear or become insignificant if they are allowed to sit and wait.
That is not true of personnel matters. Most, if not all, personnel matters get worse over time. Over time can mean minutes or hours.
I learned from some very good managers that any personnel issue should be dealt with immediately. Not quickly, not promptly but immediately. Robert comes into my office and says that the sales manager wants him to do something I have told him not to do.
I stop what I'm doing and immediately take Robert with me to the sales manager to discuss the issue. Both the sales manager and Robert have the potential for making the problem worse if I leave it to fester.
The reason I lost a girlfriend, a rather beautiful redhead, was that I got entangled in a personnel problem where I was working that had to be resolved immediately. I had promised to help her move some of her belongings at the same time. I phoned to explain my necessary delay but she had no idea why a personnel problem could be more important than she. She left me that day.
She became an example of a personnel problem that could not be postponed.