Lucy Liu
I haven't watched this show since it premiered, but decided to give it a re-run and watch every episode in order. I just realised Lucy Liu shows up, and seems like she's going to turn in to Joey's love interest (he even stops dating an co-worker for her, and they kiss), and then she completely disappears.
A few episodes later Joey goes on a date with a reporter, and then enters a steady relationship with a neighbour.
Does anyone know why they just dropped the Lucy Liu story out of the blue?