When you want to know were some commit came from. For example you can make a seemingly unrelated change in a feature branch. And then later wonder why this ch

When you want to know were some commit came from. For example you can make a seemingly unrelated change in a feature branch. And then later wonder why this change has been done. Of course you could hope to find the merge into master where the feature name could be mentioned. But it’s nicer to have it on the commit. => it gives extra context to the commit