- I played the game and earned a lot of KP which I used to unlock various things like stages, skins, etc.
- Then I went on to play some other games.
- I let another person play my system on their own Live account, but my account was still signed in, it just wasn't the active account.
- While that other person was playing, Kinect randomly decided to make my account the active account. This ended the other player's match abruptly.
- The other player returned to the dash and switched it back to his own profile and went on to play more of Killer Instinct.
- When I then later used my account and tried to play Killer Instinct, all of my progress was gone. All KP and unlocks were reset.
I have now turned off the ability for Kinect to sign users in. It's unfortunate, because I do like that feature.