After the first one lost some beads, and I realized how shitty the sewing job was that attached them, I took all the tops and reinforced all the beads. It was time consuming to sew every bead in place, but I knew that I did a good job of securing them. The first top that lost several beads (since when one breaks off, the whole thread seems to fall apart) had all the beads removed and it still looks nice, just not as nice as with the beads.

Needless to say, whenever I see one of these tops in a store, I will no longer even buy them....but that only works for the future.

There is a sewing product called Fray Check, used to keep edges from fraying, and it also helps keep stitches from unravelling. Not expensive. You could apply some to the stitches. If you can't locate it, you could also use some white glue (perhaps water it down a bit).