Having someone on the business side who has the time and inclination to work with the team is critical. Adopting agile methodologies, scrum requires changes on the business side of the development, not just the technical side.
An engaged business sponsor can help the team if it needs to push against entrenched business process, departments, or individuals in delivering valuable outcome to gain competitive advantage in the era of disruptive market. Business Sponsor, is the one who understand the market needs so as he is the person who promotes the success of the project who gets what is expected. Business sponsor accepting and giving positive feedback to team saying present project delivered more than past project will work wonders and help in getting more sponsors.
Book:SUCCEEDING WITH AGILE Software Development Using Scrum by Mike Cohn