For a workflow system to work then users need a way to see what they have to do.

Currently in the merged code there is an option in the content plugin to be emailed when there is a change in the state of an article.

This is not a workflow notification system. The email will be sent to all admin users who have been set to receive system emails.

The email will simply say
Subject - "Status of article has changed"
Body - "The status of an article has been changed by 'brian' entitled 'The News'."

It doesn't tell me if that means I have to do anything. For example if the state was changed to "Needs Review By Legal" I would receive the message even if I am only the graphic designer who should only be notified if the state was changed to "Add graphics". The user should only receive notification for something that they need to do.

In addition relying on email alone is not productive on a site with frequent content creation as I have to refer to my email every time to find the name of the article I need to update/review. This is easily resolved by the creation of a "dashboard module" so that the user can see all the content items that are in a "state" that the user is supposed to be concerned with. If you look at the privacy component waiting to be merged into J3 you will see an example)

(I wrote about this on my blog previously https://brian.teeman.net/joomla/886-content-workflow-in-joomla)