In the days before modern harbors, a ship had to wait for the flood tide before it could make it to port. The Latin term for this situation was ob portu, that is, a ship standing over off a port, waiting for the moment when it could ride the turn of the tide to harbor. The captain and the crew were ready and waiting for that one moment for they knew if they missed it, they would have to wait for another tide to come in.
In sales we are always looking for opportunities. When we miss an opportunity we often find ourselves waiting much longer for unlike the ocean tides, that next opportunity is not as easily timed or anticipated.
Worse yet many of the harbors we seek in sales only have room for one ship so if another crew gets in ahead of us our voyage must turn for another destination.