People often ask does it matter how yarns are carried across the back of the work?
The simple answer is, yes it can make a difference.
In the photo above:
On the top line the grey yarn is always carried OVER the red yarn. The stitches are small and some are not clearly defined and some parts of the stitch are ‘hidden’.
On the centre line the grey yarn is always carried UNDER the red yarn. The stitches are clearly defined as the yarn being carried is slightly slacker than when it is carried over the other yarn.
On the bottom line the grey yarn is carried RANDOMLY sometimes over and sometimes under the red yarn. The stitches are uneven, with some being much smaller than others.