I've had 4 rejected take-offs in 18 months. 3 at low speed just after take off power was set, and only 1 close to V1.
2 of the low speed rejects were for a caution light illuminating (AC Gen both times), and the 3rd was a "stop" instruction from tower due to FOD on the runway.
The high speed reject was for a possible bird strike (3 crows fighting on the runway and the skip thought they may have hit the no1 engine as we passed).
All complete non-events, but it seems I now need to get my average down somewhat.