Natasha feels hollow when she doesn't see Daniel in the lobby or outside. She doesn't want to leave the building. She makes it clear that she doesn't believe she and Daniel were meant to be, but she was looking forward to maybe going on a date with him. She wonders how his interview is going and takes one final look around that seems almost instinctive. When she notices Daniel, she reasons that her subconscious spotted him when she looked around the first time.
When Natasha reinterprets her "instinctive" look around the lobby as being the work of her subconscious, it shows her trying very hard to deny the existence of destiny. Instead, she tries to make it make sense in terms of science, which she still believes will never change or betray her.