Call it what you want, but this is how to roll tube ends to get the most out of your glue, putty, etc.
Second, press down on the area around the fold.
Third, squeeze the area after the fold. This makes room for the end fold to continue being cleanly folded in on itself.
This helps to ensure that when you squeeze a tube, whatever's inside it has one place to go - out.That way you're not over squeezing and wasting product.