What does the managing editor at a magazine do?

yes, the managing editor is typically the liason between the editorial staff and the E-I-C, which includes supervision of the editors.

It depends on the magazine, but generally the managing editor is less responsible for editorial and creative content than they are for general management of the staff—ensuring writers and editors have their stories in on time, that all work is flowing according to schedule. They also can interact with the Advertising side, and be in charge of new hires.