Last night I was knitting my little baby scarf and I ran out of yarn. Normally that really bugs me, but since I was really dying to start a new project for which I already had yarn and a crochet hook, I looked at it like an opportunity. That is, until I double checked the hook size and realized the lady at the yarn store SOLD ME THE WRONG SIZE!!
There is nothing worse than getting all excited to begin a new project only to have all of the wind let out of your sails by some stupid mistake.
Another thing that really bugs me--
Corrections. This may be a bit anal of me, but I'd prefer that you iron out all of the kinks of your patterns BEFORE* you print and sell the book. Now, I have to double check each of my patterns on the internet before I begin them. GRR.
*ok, I know that they do this, but still I think more effort needs to be exercised.