Ecommerce
Product view
Also called item view, detail view.
Product view is a recorded view of a product detail page, or an item impression inside a list. The two are different counts and should not share a name.
How it is measured
Fire an event when the detail page loads, with the product ID. List impressions are a separate event, sent when an item scrolls into a grid. Pages that open as a quick-view overlay need their own trigger or they never count.
Tarsier already counts the detail page as a pageview. A custom event adds the product ID, so you can group views by item instead of by URL, which matters when variants share one address.
Worked example
A rug retailer finds 700 views of one runner in a month and only 6 adds to cart. It is the third most viewed page on the site. A mobile test shows the photos take nine seconds to appear over a weak connection.
The shop compresses the images. Views stay at 690, adds rise to 29, and the runner moves from an embarrassing page to a respectable one.
How it differs
A product view is the look. Add to cart is the first commitment after it. A pageview is the generic load, and ecommerce tracking records the order at the end. A catalogue page can have thousands of pageviews and zero product views.
Common errors
Counting grid impressions as views. Missing variant switches. Leaving crawlers in the list. Reading views without the add rate. Comparing views between a sale week and a quiet week.
In practice
Pair views with adds for each product and look at the top and bottom ten. A page with many views and few adds is a copy, price or speed problem.