Because they can! I've always used the side of a knife (on my wedding registry from 15 years ago - who knew?) for my turtle bead mouths. The result is an open mouth, with a somewhat happy and somewhat spaced out look. Think muppets. But I've been trying for a long time to get my beads to smile. I've seen some pretty sweet tools that are curved in just the right way to make a smile, but I haven't been able to get my hands on one. A lampworker friend suggested using the end of a potato peeler, but I couldn't find one that didn't have some kind of rubber near the area that would go into the hot bead. But I loved the idea of the potato peeler, and I started looking through my kitchen drawers for something I could shape into an arch. I finally had luck with a 1/2 teaspoon (who needs the half-size anyway?). I used my pliers and bent the handle into a smile. I was so excited that my turtles (the ones with mouths, anyway) would now be able to express their gratitude to me for creating them ~ with a smile.
It's a little harder to see the smile on a lapis blue alien. I'm learning which glass is happy glass.
I can't take all the credit for the smile on the turtle at the top of the page. It's so happy because its shell is covered with rainbow Smudges murrini by rosebud101.