Color is more unlikely to "bleed": With balayage, colorists use a barrier in between their sections to stop the layers of bleach from touching. "The benefit of working with cotton or saran wrap in between sections is to forestall the lightener from bleeding, which could produce a blotchy dye occupation," https://augustivfpy.techionblog.com/31499795/balayage-braun-blond-can-be-fun-for-anyone