Why do advertisers look at detail page views?

This metric helps advertisers understand the impact their advertising has on brand halo sales.
This metric helps an advertiser understand whether their ads are driving customers to find out more information about their product.
This metric helps advertisers understand how many purchases are being made of specific ASINs.
This metric helps advertisers understand the number of impressions served.

The correct answer is:

This metric helps an advertiser understand whether their ads are driving customers to find out more information about their product.