When reviewing a commit I’m not interested in what you did. A commit is a codebase transformation. I’m interested in what will happen to my codebase when I apply your commit.
Bad “I did this” form:
I had a cup of coffee, went for a walk, and changed some code.
Better “This commit does this” form:
Adds unmap() to the command map API.
A commit message should describe the commit, not the process you went through to create it – it is not a diary.