Found the culprit

Think I've sussed why I originally abandoned my brown and green cushion cover. I'd miscounted and so a green square was a stitch out - I suspect that I couldn't be bothered at the time working out what was wrong and gave up in a huff.

But filled with new enthusiasm, the mistake has been remedied with the removal of the (now very wavy) piece of wool and I'm now taking much more care. It's not as if it's a difficult counting exercise - there are only 9 stitches in each part of the outer squares...