I spoke with someone who wants a senior level management position. (He's currently a mid-level manager.) I asked him about his experience with assistants. “I've never had one.”
Oh. Senior people have assistants because they need them. Other people need them, but our organizations have decided we can do all the grunt work ourselves. Don't get me going.
A great assistant can make you or break you as a senior manager, because an assistant will make or break your ability to finish your work. That assistant can also make it possible for your managers to succeed or not.
A manager's time is valuable, and while a manager can amplify the work of his or her staff, a manager's assistant can allow the manager that time–especially time to think. When the assistant takes on the nitty gritty details, the manager is free to focus on the big picture or to dive deep where necessary. But you can't do that unless you have a great assistant.
Great assistants can make the organization hum. Bad assistants can drop it to its knees. I was a project manager once in an organization where the assistant had her favorites. Luckily, I was one of them. I got what I needed: help from the facilities group, my contractors' invoices were paid on time, I got the conference rooms I needed, and more. But she disliked one of my colleague project managers, and he didn't get those things. He found it difficult to keep his projects rolling–not because of the technical work, but because of the environmental issues.
Turns out, he was fired later because he was a jerk 🙂 She'd given her boss feedback about this guy (and feedback to his face) for several years, and finally stopped working with him when his jerk-iness got so bad it interfered with her ability to help other people. So she stopped helping him.
I stayed in touch with that assistant until she retired. For her entire tenure at this organization, she made the organization hum smoothly. Her boss made great decisions, because he had time to think.