Finishing buttonholes

I am kntting a cape. I know how to make button holes as I go but it says at the very end to “finish the buttonholes” What is that?

If a buttonhole needs “finishing” I have used two techniques. Using the yarn I knit with or perhaps a matching yarn a bit lighter if it is very heavy, do an overcast stitch LINK around the edge of the buttonhole. Or… do an actual buttonhole stitch like you do for hand sewing.

The kind of buttonhole I would be most likely to deem needing “finishing” would be a yarn over buttonhole, but it will strengthen most buttonholes.