Measuring success based on a customer's click of an ad/email/etc. and conversion is called . The entire value of the conversion is placed on the marketing channel that delivered the customer.

Measuring success based on a customer's click of an ad/email/e.t.c and conversion is called conversion rate

Explanation:

This is an online marketing metric that tracks how successful an ad/email was

viz-a-viz the desired result of getting customers to buy a product or service.

It is calculated as follows:

Number of people who completed an action such as purchased divided total ads clicked/emails delivered.

This metric is also very in order to decide  whether or not email or ad advert is right channel to connect the customers.

answer; depth;

answer; closing the loop;