Sticking to standard sharp-cornered bar shapes ensures clarity and precision, making it easier for viewers to accurately compare data. Sharp corners provide a clear endpoint for each bar, minimizing visual ambiguity.

However, the exception to this rule is when you're aiming for a specific aesthetic or thematic effect. For example, rounded corners might be used to soften the visual impact of the chart or align with a particular design language, but this should be balanced against the need for clear data representation.