Facebook's Ad Manager and Google Analytics often report results that seem to have discrepancies. Below, one particular case, and possible explanations.
Facebook: We have 50k+ unique impressions, and 1335 clicks
Google Analytics records only 455 page views, 403 users
And only about 20 doing any sort of Engagement like scroll or click (if we read it correctly)
JS: main reasons [DR: slightly edited[
1. "Do they click the ad and shut down before page comes up?" Yup! Closing the page before the redirect fully loads. Facebook will be as generous as possible with their click reporting.
2. ... If a user clicks on the FB ad twice within 30 minutes, then Google Analytics would record that only as a single user and a single session.
3. If a user has JavaScript disabled or doesn’t accept cookies, then Google Analytics doesn’t track.
Leticia at Facebook: can be mistaken clicks, this is common.. need a pixel to fix this ..., can change it to 'landing page view'