Why does the imported cost data in Google Analytics is lower than when displayed on Facebook?

When you import costs from Facebook, service OWOX BI Pipelines takes into account the costs of:

• Clicks to website and website conversions 
• Video views (with a link to the site)
• Offer claims
• Event responses (with a link to the site)
• Carousel ads (supported partially)
• Dynamic ads
• Image promotion (Instagram)

It does not take into account:

• page post engagement
• page likes
• app installs
• app engagement
• local awareness