Ideally they would know where they are. Charts, GPS, local knowledge all have their place.

But it isn't uncommon for people to just get in the boat and go. Sailing or paddling in a small boat it isn't entirely out of the question because your not going too far. A little common sense and knowing where you started from might be good enough.

On the other hand in anything but the smallest and weakest power boat it is easy to start digging the wind in the hair and feel of the sun and the spray and only later discover that your many miles from where you started.

It is also pretty common to get lost. Coastlines can be quite complex in spots and they don't look the same way in the afternoon they did in the morning. It is easy to get lost among the many inlets, islands and multiple channels through the marshes.

They should have been better prepared. But people are always getting in over their heads. Only people who don't do anything avoid mistakes. The coasties hear this sort of thing all the time.