I'll be clear... Magento is not good as you could imagine. In fact sucks in so many ways.
Today i'm showing you one. There is no backend option to change the Default Sort Order in your product listing (catalog).
Lucky there is an easy solution.
Look for the file toolbar.php located in:
Create the Local folder
Create the same folder structure in the local. Now the future upgrades will not affect your changes.
Should be like:
Edit the Toolbar
Now you have to change 1 single
/** * Default direction * * @var string */ protected $_direction = 'asc';
And change it for:
/** * Default direction * * @var string */ protected $_direction = 'desc';