Not all Waffen-SS men had the tattoo, particularly those who had transferred from other branches of the military to the Waffen-SS, or those who transferred from the Allgemeine SS, the "General" or non-military SS.
Although the tattoo was widely used in the early war years, over the course of the war it was gradually applied to fewer and fewer soldiers, and towards the end of the war having the tattoo was more the exception rather than the rule.