Crocodilians are exceptional ambush predators, just like the great cats.

This was as stupid as turning your back on one of the great cats. They're all opportunists. They'll go for it. People like to make a big deal about how you can just tape a gator or croc's mouth shut because they have a weak open force. But they're more than capable of doing a very quick death roll and twist your arm off in a few seconds if they do get you.

The more you resist, a natural instinct, the more effective their spin is.