Increment or Add/Remove Buttons

I'm designing a software and the first version was designed by my client. During a presentation of the progress, he asked me why I removed the "Increment Buttons" (not sure if that is the right name) [image-1] and used "+ Add Branch" and "Remove" instead [image-2] when adding / removing options from a list.

Honestly, I didn't had an answer that I could prove with research but I would appreciate I someone could point me something.