Well, clearly the shot is under-exposed. Probably had something to do with the bright light in the background and white and reflective foil decorations and such all coming together and conspiring to make the camera's internal meter think the shot was brighter than it actually appears to the human eye. In response, it decreased the overall exposure.
Remember it's not the job of the light meter to calculate the exposure you want, its job is to give you a consistent base-line of exposure (based on middle grey) which you use to calculate the exposure you want. Looking at the histogram would have shown you how to correct this. If you took that shot that in raw, I'm sure it would correct easily. Possibly in JPG as well, but obviously not as cleanly.