Why did Gabriel invent the term "quiver"? A quiver in representation theory is what is called in most other areas a directed graph. Does anybody know why Gabriel felt that a new name was needed for this object? I am more interested in why he might have felt graph or digraph was not a good choice of terminology than why he thought quiver is a good name. (I rather like the name myself.)
On a related note, does anybody know why quiver representations, resp. morphisms of quiver representations, are not commonly defined as functors from the free category on the quiver to the category of finite dimensional vector spaces, resp. natural transformations? 
Added  I made this community wiki in case this will garner more responses. 
My motivation for asking this is that one of my students just defended her thesis, which involved quivers, and the Computer Scientist on the committee remarked that these are normally called directed graphs and using that term might make the thesis appeal to a wider community. Afterwards, some of us were wondering what prompted Gabriel to coin a new term for this concept.
 A: Gabriel actually gave a short explanation himself in [Gabriel, Peter. Unzerlegbare Darstellungen. I. (German) Manuscripta Math. 6 (1972), 71--103]:

Für einen solchen 4-Tupel schlagen wir die Bezeichnung Köcher vor, und nicht etwa Graph, weil letzerem Wort schon zu viele verwandte Begriffe anhaften.

Attempt at translation: For such a 4-tuple we suggest the name quiver, rather than graph, since the latter word already has too many related concepts connected to it.
(This is community wiki, so anyone can add a proper English translation.)
A: Here is some speculation. Some abstractions in mathematics can be used to study so many different things that even when you use the same abstraction you might want to give it a different name to indicate what sort of thing you're actually studying. 
In other words, the name you use declares an intention: when you say "quiver," you're declaring an intention to study quiver representations or quiver varieties, etc. When you say "graph," on the other hand, you might instead be declaring an intention to study algorithms for finding shortest paths or a million other classical graph-theoretic questions.
As another example, consider the different things we might call a functor $F : C \to D$:


*

*A "diagram (of shape $C$)." This declares an intent to talk about the limit or colimit of the functor. Here the emphasis is on $D$, or perhaps $F$. 

*A "model," a "representation," a "module," or an "algebra." This declares an intent to study and emphasize $C$, or perhaps $F$, by drawing an analogy to, respectively, models of logical theories, representations of groups, modules over algebras, or algebras over operads. 

*A "presheaf" (when the functor is contravariant and lands in something like $\text{Set}$). This declares a few possible intents, like an eye towards sheafification or a perspective that $F$ should be thought of as a generalized object in $C$. 


It's a shame that we don't have mathematical nomenclature explicitly dedicated to declaring intentions like this, but using different terms for the same thing is better than nothing. 
A: When doing my thesis it seemed it was simply because multiple edges and loops are allowed when working with quivers and therefore it is easier to use this well defined term rather than referring to it as a directed graph which seems to have a much broader meaning.
