Interesting research from eMarketer that only 15% of the people that see an advert on social media actually buy.
Where as 65% of people click on the ad to learn more.
Everybody I speak to about Facebook Ads (apart from people who, of course have a vested interest in selling you ads) tell me that if they see an ad that interests them, then they don't buy but go to the market and investigate.
For example a friend of mine purchased a handle for his iphone so he could take videos for marketing. He hadn't thought about buying an item until he spotted an ad. Which is good interrupt marketing.
The problem for that vendor is he spotted the ad. Decided he wanted such an item, researched the market and purchased a competitive brand.
The first brand continued to market to him after he had already purchased the competitive product.
While social commerce is evolving, it hasn't taken off. According to a recent survey of US internet users ages 18 and older by Survata for Sprout Social, just 15% of respondents said they were likely to buy directly from a social media ad that caught their attention. Many either click to learn more or simply like the ad.