Do you understand how view-through conversions work?
In some cases, conversions that Facebook reports result from people who never clicked on your ad. There are a couple of primary times when this happens.
First, someone sees your ad. They were interested in your product. They never clicked it. Later that day, they Googled your product. They went to your website and converted.
Another happens when you're remarketing. You target someone who is on your email list. They are served your ad but don't convert. You reach them with an email later that day. They act on that email and convert.
In both cases, Facebook knows who was served the ad. They know who converted (due to the pixel and API). They connect these two things to give your ad credit for the conversion.
