Slip first st of every row - I know HOW, but why?

[defenestator]

Hello - I'm knitting these cuffs
http://www.lionbrand.com/patterns/kf...cessories.html
you knit a rectangle then sew it into a tube. It says to slip first st of every row - I know HOW, but why? Is this to facilitate the sewing up?
alison :?:

[roxyquiksilver34]

I always slst the first st on a row b/c it keeps the edge neat and tight, IMO easier to sew up or looks nicer if it's the free edge

:D