So if you are old enough to remember when the N.E.S. (Nintendo Entertainment System) came out in 1985 in the USA, there is still a better-than-average chance that you don't know what R.O.B. is. This is because this relatively useless and expensive accessory was only available to those who decided to buy the deluxe pack.
R.O.B. was an acronym for Robotic Operating Buddy and it was simply an intermediary for pressing buttons on the 2-button NES pad. The robotic unit would actually respond to flashes that took place on the screen but a vast majority of what he did was controlled by you in an extremely limited amount of ways.
There were only 2 games ever released for this little guy, and the one that most people are familiar with is Gyromite
Basically you would use your first game pad to take a disk and load it into a rotating mechanism, get it spinning real well and then set the disk down on the corresponding red or blue plate that would now hold that button down in order to open or close the various red or blue doors in the game, allowing the "professor" to proceed. If you took too long to get mr professor moving, the spinning disk would eventually lose momentum and it would fall. It may not sound frustrating in the way I am describing it, but it was extremely frustrating.
This could be combined with the fact that if you simply bypassed the stupid robot thing you could quite easily press these same buttons and hold them with your fingers and get through any level pretty easily - which is what any self-respecting 10-year old would do when faced with such a conundrum. Then, after you had thrown R.O.B. across the room for not doing his job correctly you realize that you broke him, and then you hid him in a closet so that your parents wouldn't get upset with you for destroying this unnecessarily expensive and useless part of your console pack.
It was widely regarded as one of the craziest video game controllers and some critics say that it was unfortunate that only 2 games were ever made that it was intended for.
So why did they do it? I don't have any idea. I only had 2 friends whose parents were wealthy enough to purchase something like this and even they quickly realized that their kids don't have anywhere near as much patience as is required to play a game using a simplistic robotic intermediary.
Plus, the fact that the NES was released with Super Mario Brothers, arguably the most revolutionary game ever made, resulted in R.O.B. being relegated to the back of the closet in perpetuity.
To see how unbelievable slow gameplay was when using R.O.B. here is a 6 minute video of a guy doing the last level of Gyromite using the robot buddy.
Overall, there wasn't much use for this thing but it did become an iconic part of the Nintendo universe and has been featured in many cameo roles in movies and TV shows.
It just goes to show that just because something isn't terribly useful doesn't mean it can't be an iconic part of the history of one of the most powerful forces in gaming on the planet today.