Optimizing marketing campaigns - to determine customer responses to marketing campaigns or purchase patterns.

Improving operations - to better manage inventory and other resources, or to set prices for services based on things like seasonality.

Fraud detection - to monitor activity and note or catch unusual or out of the ordinary customer activity, often in real-time.

Reduce risk - Merchants, such as car dealers, use more than just a credit score now to determine whether to approve a loan. They also look at things like insurance claims and driving records to determine if the buyer is a risk.

Retail - Probably the largest sector to use predictive analytics, retail is always looking to improve its sales position and forge better relations with customers. One of the most ubiquitous examples is Amazon's recommendations. When you make a purchase, it puts up a list of other similar items that other buyers purchased.