Cat pee

My cat peed on the living room carpet today. Twice! She had peed yeterday and Robert cleaned it up. Then she peed in the same spot today (I think Robert did a half-assed job of cleaning it and she could still smell her potty area). Then she peed in a new different spot on the carpet. I do not understand why she insists on peeing on the carpet. At first I thought it was a ploy to keep me from exercising. It was one of those rare moments where I was on the treadmill the first time she did it today. So I got off the treadmill, cleaned it up, got back on and resumed my super-slow walking pace. The second time she peed I was helping myself to some ice cream, so I calmly placed it back in the freezer and ran to clean up her mess. Each time I see her doing it I try to grab her before the stream starts coming out, but it's too late. When she's done I grab her and race to the room where her litter boxes are, but she doesn't care. She looks at them and goes back to her sleeping spot. Robert said he's thinking of putting a litter box in the living room. I really don't want the first greeting as we walk into our house to be stinky litter. What is up with this cat?