Taking off on a wave that is already being ridden by another surfer. Dropping in is a crime in the surf world.
When a surfer takes off on a wave that somebody else is already riding: a SERIOUS breach of surfing etiquette. Remember the surfer nearest the breaking part of the wave has right of way.
Take off on a wave with somebody else already on it
To take off on a wave when rider is already surfing
Dropping in is a crime in the surf world. A drop-in is where a surfer catches a wave where he / she does not have priority. I.E. there is already a surfer on the wave. Please see diagram above. Remember - it's a CRIME
taking off on a wave that another surfer has already ridden