If you're doing something right, and it's making an impact, your competitors will pick up on it. If your competitors start changing their own strategies and tactics, and if it seems like they might be doing this in response to your campaign, it's worth looking into. Identify your main competitors and analyse how their own email messaging has changed (if at all) during your campaign.
Technology has a significant impact on consumers’ expectations, and those expectations impact how subscribers engage with your email marketing. Brands need to continually demonstrate that they know their customer, which can make it a challenge to stay on top of the evolving context of marketing. An email strategy can make all the difference between building a relationship with your customers and sinking without trace.