If your date ends at 10 p.m., you're probably not having sex. But if it ends at 3.a.m., your prospects are considerably better. It's not just that your sobriety will be long lost by that hour (though, that doesn't hurt), it's more so the feeling that a long date has.
If you're bouncing from spot to spot, the night feels wild and carefree. It makes your date seem like a whirlwind of fun that's non-stop because your chemistry is just that electric. Each subsequent destination is leading to your bed like a trail of breadcrumbs, so when you finally suggest you have the next drink at your apartment, it's a natural progression. And when things move from the couch to your bed, it seems like an extension of the night's spontaneity, a domino effect that works in your favor.