- View Content
- Add To Cart
- Initiate Checkout
- Add Payment Info
For an e-commerce site, why would somebody ever use any other conversion type besides "Purchase" for Facebook to optimize your advertising for you? Isn't the purchase all that really matters?
I can understand analyzing the paths taken through the site with an analytics tool to see where you're dropping customers, but the only reason that I could think why the others may be helpful is if you have low traffic and you're not getting any purchases. Then you'd select "View Content."