You have the option of defining a project status and a sub-status for a project. There are three options – "Pending", "Active" and "Archived" – for the project status. The sub-status offers several options, e.g. the quote phase, documentation or end phase. Unlike for the project status, for the sub-status these can be adjusted, deleted or re-created.
This gif shows you how to do this.
How you delete a sub-status can be seen in the gif below: