Discrepancies between to platforms like LinkedIn Ads and Google Analytics can vary from 5-40%. The lower end is more acceptable, especially when considered across a larger amount of clicks.
It could be higher fro any number of reasons which can include:
- Accidental clicks
- People hit stop before the page has loaded, or close the tab
- People load the page but the analytics didn’t load before they left
- Too many scripts loaded by the destination page
A reasonable click discrepancy is >15%. If it is a lot higher you may want to adjust your campaign, either the settings, the creative or the destination page.