Help me with household help/maid situation. Am I doing something wrong?

I am generally very understanding and patient with everyone, and it takes a lot to make me angry or frustrated. However, when it comes to household help lying, I almost lose my calm. I feel I can handle situations diplomatically and get the work done, but I often choose to fire them because I don’t want to deal with this attitude repeatedly in the future. I see it as a pattern that will keep popping up, and I want to avoid any drama. A friend suggested I should be more diplomatic and manage things differently. Am I doing the right thing by letting them go, or should I try to handle the situation diplomatically as my friend suggests? I struggle with being ‘in the middle’—I’m either gentle or strict. How do you handle such situations with household help? What are your rules?