Definitions
Given a digraph $D=(X,U)$, a point-basis of a digraph $D$ is a minimal vertex set from which a dipath exist to every vertex in $D$. An arc-basis is a minimal arc-reaching set. A subset $S\subseteq X$ is an arc-reaching set of $D$ if for eevery arc $(x,y)$ there exists a diwalk $W$ originating at a vertex $U\in S$ and containing $(x,y)$. The bases do not necessarily exist for infinite digraphs.
Source is the publication here and the definitions in its abstract.
I am interested in finite digraphs and I cannot yet understand the motivation for arc-bases, whence the question.
My intuition of an arc-reaching set is a vertex set from which a dipath exists to every vertex. By doing so it visits every arc, so is an arc-basis a point-basis?
Breaking this down now into the question and its relevant parts.
When are the arc-bases and point-bases different for finite digraphs?
Is every arc-basis a point-basis?
What is the motivation to define two kinds of bases for digraphs?
Which bases are relevant for finite digraphs?