A game is a set of rules that determines a winner. If following said rules to determine that winner is leads to a positive experience (fun, enlightening, enthralling, engaging, deliciously agonizing, whatever it is that makes an experience positive for you), then its a good game. If it isn't, its a bad game. The intent of the creator is entirely irrelevant. If you aren't trying to win the game, even if you are using the game components and procedures, that isn't really playing the game so whether or not that is fun has little to do with whether or not the game is fun.
For example, I once tried to teach this kid how to play bridge. He didn't get it. Or maybe he did and didn't care. Anyway, when it was his turn to bid he would just scream FIVE HEARTS!!! or SIX CLUBS!!! His team would invariably lose every hand, but he was smiling and giggling the whole time. I'm sure if you asked him his opinion of bridge he would say he loves it, but I'm pretty sure he just loved screaming, listening to everyone else groan and throwing cards on the table. The fact that their was a game called bridge being played at the time was tangential at best. If I wrote a new activity called "Smiggoblin" that involved dealing cards and yelling out funny nonsense words while throwing cards at the other players, he probably would have liked that even better.