During our experience with editing journals, we have noticed the need for a new editorial decision: WIthdraw submission, although it’s unusual.
The reasons may vary, but mostly due to a long period of review, too many rounds or difficulty in correcting the article.
This would allow us a more precise metric in terms of rejections, but it may seem too much of a detail for a lot of work to implement, as it would require e-mail templates and other controls in programming and database (maybe?).
I’m not sure if other journals have experienced this.