Engagement rate gives a far more accurate picture of what is happening on Facebook
When the rest of your competitors are focusing on the number of likes, you should be focusing on engagement. Most people like a page because they see their friends do so or because they liked that particular brand at a certain point in time. Most people forget about the pages they liked so a high number of likes on a page does not necessarily mean that the brand is doing well.
Even with very high numbers of likes, many business pages see few interaction with fans and followers and their content goes mostly ignored. On the other hand, when a high number people are talking about the brand, even if the number of likes is relatively low, it means that more people are mentioning the brand on Facebook, liking its content, sharing its content and generally recommending the page to others. As a result, a high engagement rate is much more valuable than the number of likes. The engagement rate shows you how many people are connecting with your brand and how often and a high engagement rate means that more people are commenting, liking, sharing and mentioning your brand and its content.
A high engagement rate means that the potential reach of your brand is much greater. Instead of worrying about trying to get more people to like your page, you should work harder on trying to get them to engage with your content more on Facebook.