The last comment by the manager suggests that he

Manager: Mr.Mbu, I would not describe you as an inefficient worker; I therefore find it difficult to understand why the conference room is so untidy, in spite of the fact that I had reminded you of the meeting scheduled to take place there this afternoon.

Secretary: Sir, I did instruct the cleaner to tidy up the place before meeting

Manager: Are you trying to hold the cleaner responsible for the untidy condition of the room?

Secretary: Partly, sir, I gave him an instruction which he failed to carry out. It is certainly my intention to make a formal complaint against him for dereliction of duty.

Manager: And would you wash your hands off any blame after that? Do you think that just making a formal complaint against the cleaner absolves you of all blame? When do you consider an assignment as properly executed; when the execution is properly supervised or not? Was it sufficient for you to give instruction to the cleaner with out ensuring that he actually carried them out?

Secretary: Sir, I do not see what else I could have done, short of doing the job myself. The cleaner Is a six-footer and I could not have intimidated him physically.

Manager: I see, I await your complaints against the cleaner, but I shall not forget that you allowed a board meeting to take place in an untidy conference room.