They don't know in advance how long the wait will be, and time that has already passed is a sunk cost, so they are stuck waiting "another couple of months" over

They don't know in advance how long the wait will be, and time that has already passed is a sunk cost, so they are stuck waiting "another couple of months" over and over again. There is a survivorship bias in this story because we don't hear about the (presumably much more numerous) sailors in similar situations who got paid after a much shorter wait.