Question (Q) Is some level of shirking acceptable if it is not killing the team?
Answer (A) It may not kill the project; however, it is killing your credibility with your team and your reputation in the company. A project manager worthy of the title of team leader faces this kind of problem head-on. As the leader you are paid to get people to pull in the same direction and deliver. If you can't bring yourself to do that, you shouldn't have the role.
Q How do you improve performance when you have accountability but little authority?
A First, verify your assumption that the member is lazy. You may be dealing with any number of issues other than poor motivation. Once you categorize an employee with a negative label, that judgment determines how you interact with the person, whether you verbalize your feelings or not. Then when the individual responds defensively, you have moved the discussion into the emotional realm, and you won't get anything accomplished.
Q How do I deal with an employee who isn't carrying a full load?
A Sit down in a private location and discuss the specifics - missed deadlines, unmet deliverables, and unavailability - and provide detailed examples. You may discover the employee has too many competing priorities; you may need to talk with her/his manager to adjust the workload. If employee competencies do not meet the skill requirements of the assignment, shift responsibilities.
Q What if work group participants are not putting in enough effort?
A Have regular meetings where each participant updates assignments publicly. Peer pressure motivation comes into play as everyone on the team gets to know who delivers and who doesn't.
Q What if the task force member still lags behind the team peers?
A This requires a conversation with the member's boss. Focus the conversation on the project, especially the parts that are at risk of failing, and how that is related to the quality of the person's contributions or lack thereof.
Q Won't the project or team member be angry that you went to her/his boss?
A Yes. You might have to request that the individual be removed from the team. As the project manager, you will want to redistribute the work and go short-handed rather than risk infecting other team members with a contemptuous attitude. These actions will enhance your credibility with team members.
Q What do you do if removing someone from the work group is not an option?
A Act decisively and sideline the person by giving her/him tasks that are not critical to team goals. Do not make the shirker's workload lighter, just different. Don't hold the slacker to different standards. If shirkers don't work as hard and as long as their team colleagues, the other members of the project team will resent you.
Q What are the ways to motivate better performance?
A Rewarding exceptional performance goes a long way toward inspiring it. Compliment individuals privately and publicly. Public recognition energizes positive and healthy competition. Team praise can take the form of describing how what the team accomplished will make a difference as the project moves forward.