The back of some guy's head rather than the band on stage.
A dark and blurry photograph of a football player on the field.
A "Selfie" that is too bright and ghost-looking.
These are just some of the examples of the blessing/curse of a pocket camera's flash.
So it's great that you have an incredible camera in your pocket but when it comes to Auto Mode and the built in flash you may often roll your eyes at the less-than-awesome results.
Pocket cameras are programmed to be smart and figure out what you are doing but sometimes what you want may not be the same as what the camera THINKS you want. If that flash is on and you are trying to photograph something beyond 10 feet away, the camera will underexpose the photograph because it assumes that the flash is taking care of it, which of course, isn't true. This phenomenon leaves you with a dark and blurry photograph that will wind up getting deleted.
When you are photographing something further than your camera's flash can reach, its usually better to leave the flash off. Most cameras have a "program mode" which gives you access to options like flash/no flash while remaining mostly automatic.
iPhone cameras are super simple and do a nice job even without flash but if you have a fancier pocket sized camera then you have access to TONS of features most people will never even know they have. Its really easy to just look up "how to" videos on Youtube and master your camera in no time!