There is a natural trade-off in Application design between the effectiveness of new users—who are unfamiliar with an application—and the effectiveness of power users—who have already become familiar with an application. New users need the most important functionality to be front and center, with less used functionality relegated to deeply nested menus. Power users need more features on screen at once for quicker access to functionality and information. More items on screen means less space to telegraph the capabilities of such items. Note Photoshop’s icons, or Premier Pro’s multi-use timeline.
As long as features don’t consume screen space the trade-off can be mitigated. As in the case of keyboard shortcuts, which won’t harm new users experience.
Many applications have an intended user base—either new comers or power users—but any design must still account for new users. This is often the intention behind Tour-Guides, which show up on first entry and never again. It is also possible to provide information to those who need it while hiding it by default, like in the case of tooltips that reveal themselves when an item is selected.