Stage 1: They go out on a date with a hot guy and get laid. Hope for a relationship.
Stage 2: Guy doesn't call them after.
Stage 3: They decide that the next guy will have to wait somewhere between three and eight dates before any sexytimes happen. Because this will lead to a relationship.
Stage 4: Guy doesn't call them after date two.
Stage 5: They decide that to keep a guy's interest and create a relationship they need to fuck on the first date.
Stage 6: Guy doesn't call them back after sex on the first date.
Stage 7: Me saying to them that trying to gauge when to have sex based on if it will lead to a relationship is something dudes can pick up on and if they feel you are either fucking them before you are ready or making them wait after you are ready this will make them feel like you are manipulating them into a relationship so, of course, they go away.
Stage 8: "I just met this cute guy. Do you think I'd have more luck getting into a relationship with him if we fuck on the first date or if I make him wait?"