If you have ever done an Google Ads video campaign, you will be aware that unless you link your YouTube account, you will only get limited data through to Google Ads – limited data is not what you need when optimising, ideally you take as much as you can get.
Also if you want to do a YouTube remarketing campaign, the two medias need to share data with each other. In order to link your YouTube channel to Google Ads follow the steps above!