Is ‘brand engagement’ a meaningless metric?

When measuring the success of marketing activity, the term ‘engagement’ is often used as a metric. But what does it really mean? The word has become ubiquitous yet it represents many different things to different people depending on the circumstances and campaign objectives.
For some, brand engagement can be as simple as a mention on social media or an email being opened, while others class the act of buying a product or service as the only sign of engagement.
While some ma