Explain: `git log --after=2008-10-01` has differing results, depending on time the command is run

Command `git log --after="2008-10-01"` gives _completely different_ results, depending on the time at which you run the command!!

**Example**: If you execute the command at *09:00:00* in the morning, then the result is identical to this:
`git log --after="2008-10-01 09:00:00"`

**Explanation**: If the time is not given, then it defaults to the time when the command is run. ;)