The yarn is uneven - different thicknesses. It should be the same thickness.Genuine question - can you tell this just by looking at it?
Single spun - the yarn is literally one strand that hasn’t been twisted together with other strands. It is the twist that gives it more strength. This is okay when the yarn is thinner and for delicate projects. But being that thick and used for high wear items it just will not last. It will pill and go all fluffy and worse.
and I’ve spoken to someone who tested for her. Who is an experienced knitter. The yarn is not nice to knit with. It is not a nice way to learn how to knit.