It is possible in your dataset to observe a visit with a purchased product, without getting any viewed or loaded product pages / product sheets.
This can be explained by the following behaviour:
- An Internet user visits your site and adds a product to his basket, then leaves the site.
- The next day, he returns to your site directly to the shopping cart (or at least, he does not visit any product pages/product files), then orders.
You will thus obtain in your dataset 1 purchased product, but 0 visits with products seen and consequently 0 loads with products seen.