An abrupt increase in signal strength on an OTDR trace typically indicates a reflective event, such as a connector or mechanical splice point, as these locations reflect a portion of the light signal back toward the OTDR. This causes a spike in the trace, which is followed by a gradual decline as the signal continues to traverse the cable experiencing typical attenuation. A cut or break in the cable would result in a complete loss of signal after the event, not merely an increase. Similarly, a microbend or macrobend would generally cause a non-reflective loss, characterized by a drop in signal without the initial spike. A fusion splice, if done correctly, would display a small, non-reflective loss since it is intended to seamlessly connect fibers with minimal back reflection.