Adding VR integration to a game without changing the controls and outputs to account for the increased movement on the player's part can lead to, depending on the type of game, the same player experience as without VR, at best, or at worst cord entanglement or motion sickness.
Team Fortress 2[]
TF2 was designed and released years before viable virtual reality headsets came on the general market. However, for TF2 players on Steam, there is an option to activate VR support for the game and play with a headset such as the oculus rift. The only benefit to playing TF2 with VR enabled is the novelty of VR itself. Given that the control scheme is not changed or modified for VR, players who play using VR are at a disadvantage to those who are not. For example, a player typically can not turn as fast as they would be able to using the typical controls of a joystick to move the camera. This option of using the controller rather than the headset's orientation to move the camera is still afforded to players in VR but the quick movements that don't follow with the player's own motions can cause disorientation and motion sickness.