His weapon was colors. He fought Robin, the boy wonder (back when he was literally a boy wonder) and lost. This is Robin...solo...no Batman or anything...and lost.
The guy's outfit made his masculinity look questionable to say the least. His choice of a villain name sealed the deal. Seriously, even Rainbow Raider laughs at this guy. Naming yourself after a deranged blanket really isn't the best way to forever emblazon your name into the annals of criminal masterminds forever. Instead, it's a way to become the punchline for a lot of jokes in comic book blogs in the future.
A long-forgotten DC hero who was essentially a Hank Pym knockoff, Blue Jay wins the award for the second least-scary bird-hero-name ever (Robin, is of course, the winner).
Every bird out there seems to have a hero or villain named after it (Hawkman, Red Raven, Robin, Falcon...shoot, even Hummingbird is out there), so in order to avoid confusion I guess he went with the only choice no one else wanted.
So let's stack all this up: he's a hero who is about six inches tall with blue wings and he calls himself Blue Jay. Yeah, I can see where this might cause problems gaining respect among his peers.
I'm not making this up: I was 18 before I finally figured out how to pronounce his name.
Oh, we had Plastic Man and Mister Fantastic, but who in the world thought up the name "Elongated Man". It doesn't exactly roll off the tongue, you know. Now consider that a lot of the comic book readers in the Silver Age when he came out were actually kids, and you can see where this might have been a weird choice.
Was he just trying to impress everyone with his vocabulary? Was Rubber Band Man already taken? How about Stretchy Guy or something? Tell the truth: have you ever used the word "elongated" in any conversation ever? I didn't think so.
Another Batman villain, this one just showed up for a few issues in 1973 before being taken down for good. He was originally played up as a ghost character (thus his name), but Batman's detective skills brought him down and proved he was nothing more than a talented escape artist.
Talented in escape maybe, but choosing a name? Not so much. It brings more of an image of Casper the Friendly Ghost than some criminal terror to be afraid of. The only thing you can give him is that he was able to, for one issue, outsmart the Batman by stealing the Batmobile.
Before he became a Doctor, he was...no, just kidding. This obscure villain "terrorized" Doctor Fate for a while during the Silver Age.
A brilliant scientist, he created a formula that changed his appearance, made him grow as he needed to, and even let him blend into the background colors of a room. Doctor Fate was able to beat him, as you can imagine.
But the name? Seriously, that's the best you could come up with? I can just hear an Abbott and Costello routine playing through that.
"What's the guy's name? Mister something."
"The guy Doctor Fate's fighting."
"The guy who grows big and stuff."
"The guy in with the beard! Mister what?"
"Oh never mind. Let's watch that British Sci-Fi show you like. The one with the Doctor guy. What was his name again?"
And on it goes...