Most important electronic equipment
Circumstances are different depending on where and when you sail and what kind of boat you have. I know my waters pretty well, can almost always see the bottom if it gets shallower than 15 feet, and study my charts before and during. So for me GPS is #1 followed by VHF so I can get the weather reports which I monitor every 3 hours. Two things which scare me are severe weather and meeting up with a large boat in zero or near zero visibility ( it is interesting that my main fears are about things that have never happpened to me).