Yup, I get it! It's kind of like a more fluid version of memory wire. If you bend memory wire too far in the wrong direction, it snaps. Although the snake bracelet is a lot more fluid than memory wire, there's still a certain direction that it tends to favour being curved into.
Let's say you hold the two ends tightly and bend the bracelet upwards (without twisting your hands in any way), and it easily curves in that way. However, if you bend the bracelet downwards with your hands in the same position, it doesn't bend much at all. That means you should always fasten your bracelet when it's in that fluid, easily-curving position as when you bent it upwards.
The smaller size bracelets tend to be rather hard to fasten no matter which way you curve it, but over time you'll find that it's easier to fasten it in one particular curve direction.
Did I even make any more sense than you? LOL! I think you explained it pretty well!