Knowing when to show more information and when to show less is not only good design it's good usability. The more information you present the greater the cognitive load a user has to juggle to accomplish a task. Sometimes you want to have lots of information visible to make the best choice but other times you don't. There is a point of diminishing returns where you have given your users too much information too soon. Sometimes people need to ease into an application, get acquainted with it, and then proceed to learn more.
Progressive disclosure is when information is sequenced out across several pages or screens to help a user process information and to avoid overwhelming them with too much information. Additional information, or more advanced or rarely used features, are hidden away until needed. This is a technique that was used by IBM in the 1980's when developing user interfaces. They realized that progressively disclosing additional tasks and information through a series of menus was better than having everything present up front. It managed complexity by clearing up clutter. It helped new users get familiar with the UI and as they became more savvy users they used the menu systems to find more advanced functionality.
The attached Technical Paper discusses a bit more how progressive disclosure is useful in BI. Progressive disclosure helps the DAR methodology to give users the general summary on the Dashboard, more advanced functionality on the following pages, and then the real deep dive information for Reporting. Progressive disclosure helps you design for other people at a variety of skill levels to get the most out of your applications.