I quickly typed "Mickey Mouse", then "Donald Duck". Then I was stuck for a third name. Goofy? Pluto? Distracted, I wondered: "Why don't those guys have last names, anyway?" They're both dog-like creatures (I think), even though for some reason one gets to walk on two legs and wear pants. "Goofy Dog" sounds stupid though, no alliteration. Same with "Pluto Dog". Maybe that's why they each only have one name.
My brain got totally stuck at this point, and I couldn't think of any cartoon names which weren't mice, ducks, or dogs. For no good reason, I didn't want my third name to be the same animal as either of the first two, so "Daisy Duck" and "Mighty Mouse" were right out.
Sometimes I get like this, entirely blocked and stuck on a piece of completely irrelevant information. I wanted a third name, and I couldn't think of one I liked.
Finally I typed out "Goofy Gorilla". I know, I know: Goofy is not a gorilla, but gorillas are fairly goofy-looking after all. It's alliterative, and it's a different animal than the first two. Satisfied, I was able to proceed with the more technical aspects of my prototype.