Currently a variation will be pre-selected on the landing page of product. This can cause lots of order mistakes. For example, if a customer enters the following product:
https://www.jasfashion.com.au/stretch-sleep-cap-with-fine-stripes
The person's head size is S/M.
She selects S/M first, then selects the 2nd option (green).�

�
�
The problem comes with the next step:
Then the customer changes her mind and changes to the 1st colour option (grey) and she will be automatically moved to XS/S without knowing she had been moved to a different size option.

Suggestion: Please stop an variation being preselected for a customer!