The SS were not necessarily elite. They were the political representation of Hitler in the military. This afforded them more attention and equipment, they were actually rather at odds with the rest of the BW.

The Waffen-SS consisted of both what could be considered elite divisions, and many average/mediocre or outright useless divisions, often hastily scraped together, and usually only divisions on paper, not actually battle strength.

War time Waffen-SS basically divided recruits into three categories; "SS kv", "Heer kv" and "gvH". With the first category being the best soldier material, the second being the average quality (the same standard as the Wehrmacht), while the last "gvH" consisted of the recruits not fit for frontline service because of age, lack of strength, or having slight physical defects or illnesses like stomach problems.

"SS kv" recruits generally went into the elite SS divisions, like "LAH" and "Totenkopf", while the "Heer kv" group went into second or third rate divisions like "Prinz Eugen". The "gvH" group went to very static units and becoming a KZ-camp guard was a likely result. (See Paul Milata; "Zwischen Hitler, Stalin und Antonescu" Kap. 9 for an overview of wartime W-SS recruiting standards).

Another way for a W-SS soldier to become a KZ-guard was when being wounded at the front. While recovering from the wound such a soldier weren't fit for frontline duty, but could perhaps still perform guard duties. Typically such recovering W-SS soldiers were temporarily transferred into "Ersatz" units (Reserve units), and such unit could perform guard duties at the large KZ-camps, or smaller KZ-Außenlager. Such Ersatz-units could also perform executions of Jews or other "undesirable elements" since they were under direct command of the SS, not the regular army, while in rear areas.

The KZ-camp system was wholly integrated into the Waffen-SS. Early W-SS divisons had been raised from using KZ-camp personnel, and there was a continuous transfer from the KZ-camp personnel into the Waffen-SS, just like there always was a KZ-camp or a KZ-Aussenkommando at each divisions home base, so the W-SS had access to prisoners to perform cleaning or manual labour duties.