Why Advertising on Facebook
There are over 2 billion users on Facebook which makes it the biggest social media platform. You can target this people very precise offering them relevant post ads and content they are interested to entice them to click or purchase. The clicks are most of the time cheaper then advertising on google thus it makes Facebook ads affordable for lower budget companies.
Post from friends and family are prioritised on social media platforms especially on Facebook so organic reach is constantly declining. On the other side paid ads are guarantied to be seen by your chosen audience.
Social media marketing is cost effective because you only pay when someone clicks your ad (PPC) and the average cost per click is $1,50 way cheaper than traditional advertisement. It also allows you to retarget people who visited your site and which are more likely to convert for less thus increasing your ROI.