I am a team leader of a team of six women. One of them has been working for twenty years in the firm and is used to saying whatever she wants. In the past five years the company has been introducing the lean method in order to measure and improve the ways we work.
Now that her job is measured, her under performance is not longer invisible. It also appears that she rarely has the job completed by the set deadline. When I confronted her with these findings, she explained that she always feels that she has too much work on her plate which I feel isn't true. When other team members replace her, they manage to do all her job and have some time left. So in fact she is really under performing. When confronting her with this again and asking how this could be solved, she always finds reasons to explain that she is not under performing and that everyone is happy about the tasks she is doing. She claims that we need an extra person in the group.
When she had to write her end evaluation, she only mentions the things that she did well.
So on one hand she is under performing, on the other hand she can't evaluate herself objectively.
In addition to this, she is always arguing about anything. She can never accept anything and will always go the opposite direction. She can also give her unsalted opinion on the way I conduct a situation or issue. She is always challenging me, which is really tiring, especially when I don't expect it to happen. She doesn't know her place.
As she feels that this situation has to change, and that I will no longer accept all of this, she has started to gain the sympathy of the colleagues on a very refined way. She made the colleagues believe that she is the victim, and that I don't like her, etc'. So although her colleagues know that she is under performing, I feel that they are treating her as a victim.
How do I handle this without losing the energy and trust of other team members?