Well first of all I would say that having a well optimized website is still going to bring you far more business via social media in most cases especially if you are a small to medium sized local business.
However despite all the statistics I think it is still a good idea for business. Basically SMM Companies and Business as a whole looked at social networks like Facebook as a fresh market ripe for the picking and since them a few venture capital firms have made investments into Facebook.
To get more information about social media marketing you can visit https://www.stanfelmedia.com/ or similar websites.
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Both SMM Companies and Business have failed to truly capitalize on the huge number of Facebook users online. I believe the major difference between social networks and search engines is intent. People who use Google are deliberately searching for something.
One of the biggest problems business face with social networks and SMM is perception. The primary reason most people give for interacting with brands or business on social media is to receive discounts, yet the brands and business themselves think the main reason people interact with them on social media is to learn about new products.
Companies need to find more innovative ways to connect with social media if they want to see some sort of result from it.