Why can I still view a product that has been marked as inactive?
When you mark a product as inactive, through the management system, it means that it will no longer show up in search results pages or category pages, or your website's home page (if you've chosen it as a featured product).
However the product can still be viewed by going directly to the product URL in your browser. This means that visitors to your website that come through a search engine like Google, having searched for a particular product, may still come through to the product.
Inactive products can't be added to the shopping basket on your website, so will not be able to be purchased by visitors (regardless of whether the product is marked in stock).