Anyone who grew up playing Sonic games in the 1990s knew that the lead villain was called Dr. Robotnik. He had henchmen and other subservient robots under his command, and it only made sense given his name was Robotnik... right? Wrong. Robotnik was never supposed to be his name.
GameZone singled out a quote from an interview that Game Informer conducted with Sonic Team's director Takashi Iizuka. They're currently working on a brand new Sonic game that will be unveiled this year, a new generation of Sonic. Iizuka explained to Game Informer that Robotnik was a name that Western localizers came up with but they never consulted with the design team before making that change...
When the game was originally developed in Japan, they called the character Eggman. That was the name of the character, but when the game got localized and ported into the Sonic the Hedgehog that we know in the West, they decided to, without confirming with the development team, change his name to Ivo Robotnik or just Robotnik. That's kind of when everyone first learned about the character. Of course, this was without consulting the people who made the game. They just kind of went off and did it. It became super popular and everyone in the West kind of learned about the character as Robotnik.
It wasn't just popular, it was iconic.
Everyone identified Sonic's main villain as an evil genius doctor... a doctor of robotics. The moniker Dr. Robotnik fit like a glove because it not only quickly identified him as someone who relied on mechanical underlings to do his dirty work, it also easily established him as a maniacal genius; a bright mind gone mad.
The name stayed within the Sonic games all the way through the 1990s, and was even the name used in the various cartoon iterations that came out during that time as well. Sonic and Dr. Robotnik were a pop-culture phenomenon, similar to Mario and King Koopa (the latter of which would simply become known as Bowser by the time the N64 came around).
Iizuka and the rest of the developers were not pleased with the change in name. They had made the oval-shaped villain Eggman and they were going to stick to it. Iizuka further explained...
[Robotnik] went on through the "classic" series in the Genesis/Mega Drive era, but as far as the developers are concerned - the ones who made the character and the leaders of what this character is doing next - we really didn't want to have anyone in the universe with two names. To us, he's Eggman, but in the rest of the world he's called Robotnik. We wanted to unify that into one name moving forward. This is something I actually did in the Sonic Adventure series. I made it so that we understand the character's name is Robotnik, but his nickname is Eggman, and as far as everyone is concerned in the world now, we're just going to call him Eggman as his official name.
It's unfortunate because Dr. Robotnik was such a unique and fitting name for the character. While th egg-shaped Eggman obviously plays on his conspicuous shape, it was the more subtle and nuanced Dr. Robotnik that won fans over.
To this very day most fans will agree that Dr. Robotnik just rolls off the tongue easier and seems both prestigious and fitting for Sonic's arch-villain.
It's also interesting because as Robotnik turned into Eggman, the games started to get worse. At this point most Sonic titles feel like parodies of the original, but Sega is promising to get things back on track with the new 3DS title Sonic Boom: Fire and Ice and the currently unannounced Sonic game due out for the new gen consoles. Sadly, if you were hoping Dr. Robotnik would be making a return, you're fresh out of luck... it's going to be Eggman forever.