Why does my yarn have a random knot in it?

Question

I bought two skeins of Crafter's Secret Big Idea cobalt blue yarn (810 yards) for a sweater that I'm knitting and the second skein had a knot that I didn't tie in the middle of it, why?

Answer 1

It is likely just a yarn knot:

Yarn is essentially a piece of string that, during the milling process, sometimes breaks. The mill isn't going to throw away good yarn because of a single breakage. So, what they do is tie the yarn together with a knot and the process carries on.

This is corroborated here:

Knots aren't tangled yarn, they're a point where the yarn has been broken and tied back together. They can be a frustrating but unfortunately inevitable part of knitting with natural fibres.

Finding a knot in a new ball of yarn can be irritating but unless you hand spin your yarn, and know where your joins are, you’re likely to come across more than a few if you regularly knit with natural yarn.

You can treat it like a new ball of yarn.