MEET LEX LUTHOR
MORRISON: Superman is us at our best, and Lex is us at our worst
but they're both us. He's selfish, he's inwardly directed, he's greedy, he's egotistical, he pretends to hate Superman but really he wants to look like Superman, he's constantly chugging energy drinks, he talks crap
[Laughs] I wanted to make him an embodiment of all our worse traits. They're what make us human, so that's what makes Lex human and relatable. That's why Lex Luthor's such a great villain: we all recognize those traits.
MORALES: Lex's weight is one of those little subliminal things. It adds a layer of jealousy and feeling insignificant and insecure about yourself. He's this out-of-shape, snide, condescending jerk who we're too mature now to stuff into a locker when we see him, but we still do it every time in our heads. [Laughs] Luthor's that guy from the electronics store who condescends to you when you ask about the difference between a megabyte and a gigabyte.
The following is a panel description from the script of ACTION COMICS #1:
Silhouetted against the screen are two of our principle players - Lois Lane's dad GENERAL SAM LANE and Superman's arch-villain LEX LUTHOR. Lane is the archetypal tough American dad. Luthor, like Superman, is a little younger, perhaps a little heavier and sturdier. I like the idea that he was a little fat until his jealousy of Superman drove him to the gym to become the trim, muscular Luthor of the Silver Age and more recent stories. So he's not obese but he's veering a little more in the visual direction of Luthor's heavier build as it appeared in stories from 1941 to 1959.