Every good business has loyal customers. But you also have loyal visitors... and even customers who bought from you before will likely circle around and take their time between repeat purchases. By systematically working on tracking and segmenting your online users, you will be able to create much more relevant ad campaigns that build loyalty.
If you look at your advertising currently, probably most of it is designed to speak to new customers. Retargeting will give you a way to speak differently to prospects who are not brand new, and furthermore give a different message to your existing customers to keep them coming back.
With effective retargeting:
increase confidence the people seeing your ads are relevant to your business
make useful product recommendations to customers
avoid showing new customer ads and offers to repeat visitors
offer special incentives to people who show a high level of interest, but haven't converted yet
improve ROI on your ad campaigns as you attribute conversion value more smartly
50-60% higher conversion among retargeted customersKimberley-Clark, 2013, via Wishpond