You should prepare meetings involving criticism particularly well. In particular, prepare the facts in a comprehensible and verifiable manner.
During the discussion, choose appreciative introductory words, but then address the misconduct unambiguously and show personal concern. Check your employee’s willingness to change and demand it. Then investigate the causes together. Agree on the goal of the change and define review criteria together. If appropriate, clearly communicate the consequences that will be imposed on your employee in the event of repeated misconduct. At the end of the discussion, summarize and document the results of the discussion. If necessary, have your employee countersign to emphasize the binding nature of the agreement reached.