People are more driven to finish a task as it nears completion. This is known as the Goal Gradient Effect. An example of this working in real-time is a sandwich shop giving away a punch card that offers a free sandwich after your tenth purchase, but with the first two holes punched. People consistently prefer completing eight tasks with two done for them over eight tasks with none done for them. Giving your customers the feeling of making progress will have a positive effect on their experience.