She needs to do the work she’s supposed to do.

Remember back in school, when you were assigned a group project, and there was an unequal distribution of work amongst group members. It’s common for members of group projects to sit back and let one person take charge, leaving that person to do most of the work. It’s frustrating when you care a lot about your grade and are willing to do whatever you need to do to maintain it, but it seems like none of your peers feel the same way. The truth is, your peers can tell by your vibe that you’re not the type to drop the ball on a major assignment, so they rely on the correct assumption that you’re not going to leave the project incomplete if they don’t do their sections of it. 

You find the same personalities in the workplace all the time. They know their overachieving coworkers will pick up the slack, so they don’t feel a sense of urgency to complete their work on time. They’re happy to let someone else take the lead on their project, especially when their boss hasn’t given them a specific list of tasks that they personally need to complete. If anything, this problem is worse in the workplace than in school. In school, your professor might ask group members to anonymously report how the work was divvied up or whether anyone didn’t contribute at all. At work, you’re not going to get a failing grade for not getting your work done on time. A lot of times, you can get away with it for way longer than you deserve, because it’s not socially encouraged to call out your coworkers for not getting their work done in front of your boss.