You may find Apache is fully stopped and then started when doing package updates or running a cPanel update. The article covers why this may happen.
Apache may need a full stop in order to ensure it is running the latest versions of the software installed on the server. If the main Apache package, or any of the Apache module packages are updated a full stop and start will be needed. This will also e the case if certain system packages that Apache depends on are updated, such as glibc.
Lastly, if an error is encountered while determining if Apache needs a full stop and start, a full stop and start will be performed as a cautionary measure.