First line: understands that their role is to make the team better. Listens a lot, delegates decisions and projects and focuses on skills and career development and team chemistry.
Mid-level: creates a culture of trust and respect. Holds teams accountable for their performance. Sets a clear and correct strategy. Staffs the team correctly.
Upper: same as mid-level. Also, a good speaker and financially savvy.
The difference is that a first level manager is responsible for a small number of people that they can directly oversee. A middle manager has a team large enough that they can’t do that, so they need to build a culture that makes the right things happen. An upper manager is in a similar situation to a middle manager but is also responsible for public speaking on behalf of the company and for delivering financial results.