Answer
Single-decision maker tends to benefit from the autonomy to take decisions and make required amendments, whereas the disadvantages include that there may be bias and efficiency could have been improved.
Step-by-step explanation
Single-decision maker is alone to make final decision calls which permits him or her to enjoy the autonomy of their job and implement their skill set on the situation at hand. On the other hand, making decisions alone tend to permit the decision maker to bring in bias within the context of the decision and the situation in all. Therefore, it can be good as well as bad.