First, clarify some terminology, in Adwords goals:
Sales – Drive sales online, in app, by phone, or in store (“conversions” in FB)
Leads – Get leads and other conversions by encouraging customers to take action
Web traffic – Get the right people to visit your website
There are some minor differences between these 3.
“Sales“ in ecommerce world means a transaction, 99% involves money movement, and most likely a checkout process as well.
“Leads” in ecommerce site can means “add to cart” or “subscribe to newsletter” or “add to wishlist”. Usually means user expressed some kind of interest.
Obviously only some traffic converts to “leads”, and even smaller converts to sales.
Ad platforms use their AI, visitor pattern, search queries etc to guess the user’s funnel position, and help determine the user’s goal. For example, adwords may use the search query “How to use sunscreen” as a hint, link the goal to “traffic” and “leads”, but may not “sales”. In contrast, “Where to buy sunscreen” may more link to “sales” goal.
Take an example of overall conversion of 100 visits, 5 add to cart, and 1 sales, when selected “leads” and “sale” as goals, ad platform will try to drive better conversions from “higher quality leads”. They determined if the user is very likely to buy. And higher quality leads will cost more per click.
There is no rule of thumb to choose which is better. Sales goal may provide better checkout numbers, but if your site sales conversion is higher than average site, leads could provide better results.
Traffic as goal pros:
- Lower CPC
- Less setup
Cons
- “Traffic convert to sales rate”might be lower
- Need to calculate final visitor-to-sale conversion rate
Sales pro:
- Fire and forget
- Actuate results
Sales cons:
- Higher cpc
- Need more setup, as ad platform need to know your transactions
Document On Ready 