Specifically, gap loss happens when the signal from one end of a piece of cable is transferred to another, but there is a space, breakage, or gap between them. Since fiber optics transmit data via light the light can cross this gap, but spreads out and is weakened and diffused when it does so. The light that crosses the gap and enters the next section of cable is broken up. Some of it reflects off, and some will hit the covering of the cable and not enter into the cable. If the gap is small, the gap los.