The bone is broken in the centre and the two ends have caught on each other during the break so they are still touching.
Most middle 1/3 fractures heel very well, and functional outcome is the same.
You need to be very selective which ones you fix, for most the functional outcome is the same so it isn't worth the operative risk.Ones that are very displaced, or of the lateral 1/3 are more likely to be operated upon.It's certainly not a benign operation and I personally wouldn't rush into it just for the sake of it.