What is the Difference between Hiding a Measure Item and Hiding its Value?

Hiding a measure item means that the row(s) or column(s) for it will no longer display in the view grid. If you just hide the value for a measure item, then the cells for that measure item will remain in the grid and only the numeric values for it will be hidden. If the measure has a conditional format or an image defined for it, then those items will still display when the value is hidden. To hide a measure item, you set its Visible property to No. To hide just the value, you set the Value property to No.

See also Why Would I want to Hide a Measure Item Value?