The clearest signals usually leave one thing unfinished. She repeats the pass, holds the look, moves closer, delays goodbye. But she does not spell out the whole route.
That is where a lot of men freeze. They want the sign to arrive like a notification, clean and impossible to misread. In real rooms, it is messier. A friend interrupts. A drink arrives. Someone checks the group chat. The opening is there, then it starts shrinking.
She is giving him enough to notice. After that, he has to read the room, take the risk, and cross the distance before the night moves on.