In a post on the Samsung Unpacked blog, the company says there were three designs, all of which were treated as 'final.'
The company revealed: "There were three different prototypes to avoid any design leaks. All were made like final products.
"This meant making three totally different, continuously changing models in the same time frame. Engineers had to repeat the same process for all three types."
Tiring and frustrating
As an example, the device's antenna had be be designed every time a new design was implemented, according to the engineers.
"To be honest, it was quite tiring and frustrating," said Samsung Senior Engineer BeoungSun Lee.
Principal Engineer WooSun Yoon said disguises were often used to hide the device, while colleague ByungJoon Lee said the team were never allowed to send drawings or pictures of the S3 concepts and had to explain design nuances using words.
So, if you were wondering about all of those different 'leaked photos' of the device, pictured all over the web in the months leading up to launch, they were all probably genuine, to a point.
Fair play to Samsung though, the company did a fine job of throwing everyone off the scent.
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A technology journalist, writer and videographer of many magazines and websites including T3, Gadget Magazine and TechRadar.com. He specializes in applications for smartphones, tablets and handheld devices, with bylines also at The Guardian, WIRED, Trusted Reviews and Wareable. Chris is also the podcast host for The Liverpool Way. As well as tech and football, Chris is a pop-punk fan and enjoys the art of wrasslin'.