Bar charts show the bars sorted in order by their label. Sometimes you want the bars to be in ascending/descending order by their sizes (i.e. the value being measured), so that the most significant items are on one side or the other.
While we're at it, the option in the bar chart design to Limit the number of bars being shown to just the "Top X", would help where you have situations where again you want to focus on the most significant items (smallest or largest) without outliers throwing it off.
