I love this thread because I've have had both a goatee and a soul patch in the past.
(Ok, I had the soul patch for two days as a lark when getting rid of my goatee. But I think it still gets me in the double-low-class club.)
As for the goatee, which I had at various times in my teens, twenties, and thirties, it mostly had to do with (1) getting tired of shaving; and (2) not really being able to grow a full beard because my cheeks only get this Dylan-esque scraggly growth. Looks better on Connery than it did on me, though.