If you have driven down the interstate in the last 50 years you would see billboards promoting restaurants and amenities all along your trip. My favorite is the drive to Las Vegas right before you get to Jean, Nevada. You see a succession of signs promoting everything you can do when you visit the casinos in this city.
Google Remarketing works in this way as well. You know that the customer has visited your website (or intends to pass it on the interstate) and they are interested in your product/service. It is now time to convert those potential customers.
Talk directly to the customer and identify the Benefit to the Customer if they purchase. Then, create a succession of banner ads to educate them on your product/service and entice them to return and convert. For example, eBay would have banners with themes like; save money, browse a wide variety of products, ship it today, etc. Figure out what will motivate your customers and create a set of banners and improve your conversion rate.
Be sure to rotate in new banner ads on a regular basis. After 4 impressions a day, most banners become white noise. Also consider different color backgrounds since most blogs and websites are built on white backgrounds. This will give your banner ads more pop.
Google Remarketing gives you the opportunity to advertise to interested customers. Speak directly to your customers and tell them what they will get if they purchase. Don't waste the opportunity!