In my experience as a Scrum trainer and coach, I have seen too many Scrum teams that fail to do what Scrum was invented for: Inspect and Adapt.
Do the following statements describe the situation of your team?
- Little is done about problems discussed in Retrospectives.
- Sprint Reviews have no impact on what is build in subsequent sprints.
If so, you may be interested to read my article on the Scrum Alliance website:
Effective Retrospectives & Reviews.