By default, SharePoint enables top navigation Fly out Menus when Publishing Feature is enabled. Other Site templates like Team Sites doesn’t come up with top navigation flyout menus. However we can enable top navigation flyout menus by adjusting few parameters in master page.
This is also applicable when we use custom site map providers for Top navigation! Here is an example of the SharePoint 2010 top navigation drop-down menu.
Same trick works on SharePoint quick launch navigation as well to bring flyout menus. Adjust the “StaticDisplayLevels” and “MaximumDynamicDisplayLevels” values based on the navigation depth accordingly. (say: 1)
And the output goes like this:
After the change, SharePoint 2010 quick launch flyout menu appears as: