Microsoft Office applications automatically customize menus and toolbars based on how often you use commands. When you first start an Office program, only the most basic commands appear in the menus. Then, as you work, the menus and toolbars adjust so that the commands and toolbar buttons you use most often appear. This feature is known as adaptive (or personalized) menus and toolbars.
Every user needs to understand this feature fully. If you are one of the (rare) people who prefer adaptive menus, you should know all the tricks for how to access hidden commands and tools when you need them. If you are one of the vast majority that prefer to have instant access to all of your commands, you need to know how to disable adaptive menus and toolbars.