The final stage of the sales funnel is the action that you're intending them to perform. In most cases this is the purchase. Again, how well you move them through the various stages is going to set you up with a specific conversion for this action. For example, if 100 people click on your offer and 10 people enter your sales funnel but only purchase people purchase, then you have a 2 percent conversion.
One of the core concepts in the digital marketing industry is the sales funnel. While odd sounding at first, this single core concept can take a business from virtually non-existent and unknown to multi-million-dollar marketing machine with mass saturation, seemingly overnight. In fact, there are skilled practitioners who have built a career around implementing this single concept in business.