Not doing it. Some managers don't give critical feedback at all. They either let low performers remain on their staff forever, or they fire them out of the blue one day--having given the employees no sense of what was coming.
Doing it too late. Some managers ignore problems as long as possible and don't speak up until it’s become so serious that it's much harder for the employee to recover. Giving regular feedback is part of the job as a manager; those who avoid it are being as negligent as a receptionist who ignores the phone when it rings.
Not being clear enough, either about the problem or its severity. Some managers get so caught up in trying to be tactful that their message gets diluted or lost. And part of that is...
Not explaining consequences. Good managers are clear about potential consequences if problems aren't fixed, explaining that it could impact the person's next raise, jeopardize their job, or whatever the case may be. I've seen managers give lots of feedback to a struggling staff member but never explicitly say that the person's job in jeopardy--so, the staffer ends up shocked when she is ultimately fired. Not only is this unfair to the staffer, who deserves to know the severity of the concerns, but it can create significant anxiety among other employees, who may begin to fear they’re on the verge of being fired every time they receive critical feedback.
Never having consequences. Rather than setting clear standards and holding people accountable to them, some managers just try to coax and cajole employees into doing something differently. But when there aren't any teeth behind the rules, problems will often continue.
Being a jerk. While some bad managers shy away from giving feedback altogether, another type goes in the other direction--they make their feedback personal, and yell at, or demean, the employee. Good managers may sound concerned but rarely angry or hostile. They have a matter-of-fact attitude toward their authority, rather than lording it over their staff.
Not putting the criticism in context. If 99 percent of someone's work is great, a manager addressing the problems with the other 1percent shouldn't make it sound as though the overall great performance has gone unnoticed.
Alison Green is the author of Managing to Change the World: The Nonprofit Leader's Guide to Getting Results. She is chief of staff for the Marijuana Policy Project, a nonprofit lobbying organization, where she oversees day-to-day management of the staff as well as hiring, firing, and staff development. Her writings have been published in the Washington Post, the New York Times, Maxim, and dozens of other newspapers. She blogs at Ask a Manager.