The phrase "incompetent staff" means that the employees or workers are not skilled or capable enough to perform their jobs effectively. Full definition
Teacher training institutions are being accused of letting incompetent staff into the profession. (bbc.co.uk)
«We found ourselves thrilled at the news that Amazon was assuming ownership, hoping that they would be able to fix the problems, a lot of which we believed to be the result of very incompetent staff,» she told Business Insider. (businessinsider.com)
The piece is actually a re-hash of a story the New Times ran 5 months ago about private schools participating in McKay that mishandled money, hired incompetent staff, or failed to provide adequate services. (educationnext.org)