Wait for it

I got word of a worst argument in Britain contest being run at the University of Gloucestershire.

This reminded me of a billboard I once saw in Baltimore aimed at discouraging teens from having sex. Here is the billboard's text, in its entirety: "Sex can wait. Your future can't."

Now hold on a minute.

The billboard says that sex can wait.
If sex can wait, then sex is in my future.
According to the billboard, my future can't wait.
If my future can't wait, and sex is in my future, then sex can't wait.
But if sex can't wait, then this billboard is--how should I put this?--f*cked, since it started off by telling me that sex can wait.

Make up your mind, damn billboard.

UPDATE: Photo links here.