In brief
background-origin selects the reference area for background positioning: border-box, padding-box or content-box. The same offset can therefore begin from a different box.
Useful to know
background-origin selects the reference area for background positioning: border-box, padding-box or content-box. The same offset can therefore begin from a different box. [1]
Do not confuse it with background-clip, which constrains painting. Change one setting at a time to distinguish an origin problem from a visible-boundary problem.
Sources
For further detail and to check the information: