When using a bar chart which has the vertical axis based on a dimension with different values such as a sales person as part of a dashboard where the chart is not full size, the user cannot see all values of the dimension.
It would bery useful if when they hover over the bar, the value of the dimension that they are looking at is shown instead of or in addition to the name of the measure.
Similarly when a bar chart is used with a long date range, not all dates are shown
Not all user have a full license to use analyze mode and see the underlying data which makes the charts of little value to them.