No two emails should be created alike: That’s the rule that all too often companies ignore when creating email-focused marketing campaigns.
Either they’re not relying on data they have about customers, or they’re not gathering enough data and using enough planning time, but the result is that their email marketing campaigns are losing their punch.
Think about it: When you decide to email customers, do you have a goal in mind? Even if you just want to check in or share something new on your website, you have to decide what that is—then craft the email around it. 
And back to that all-for-one email: You can’t do it. It’s deadly to any email campaign. People need to feel like you are talking to them, which is why segmenting by whatever characteristic you can is so important to email campaigns. 
Via Salesforce
