From Zippy the Pinhead:
After Griffith criticized Scott Adams’ comic Dilbert for being “a kind of childish, depleted shell of a once-vibrant medium,” Adams responded a year and half later on May 18, 1998, with a comic strip called Pippy the Ziphead, “cramming as much artwork in as possible so no one will notice there’s only one joke… [and] it’s on the reader.” Dilbert notes that the strip is “nothing but a clown with a small head who says random things” and Dogbert responds that he is “maintaining his artistic integrity by creating a comic that no one will enjoy.”
05/18/1998
05/19/1998
At this point in time Dilbert was at the height of its popularity, its characters were appearing in Office Depot commercials, and there was a TV series adaptation set to premiere the following year. Imagine having all that success and still being this petty.