Will people understand what you’re trying to say? It’s usually better to avoid topics (or opinions) that are complex if many people are extremely passionate about them. For example, sharing almost any opinion about immigration policy is usually a bad move, unless your audience is unusually homogenous. You could agree 99% with someone and still piss them off by using the wrong term just because they have such a strong “either you agree 100% with us, or you’re our enemy” mentality. I once pointed out that I think it’s unacceptable to capture and torture people for years—especially if they aren’t charged with any crime, there’s no evidence they’ve done anything wrong, and they’re children. I got several emails back from people saying, “you have no idea what you’re talking about” or “you should stick to marketing and leave politics to people who understand it.” They took it as commentary on geo-politics. I just said I’m not okay with pointless torture of children. I thought we’d all agree on that.
Every week, the folks at InVision send a roundup of their best blog content, their favorite design links from the week, and a new opportunity to win a free t-shirt. (Seriously. They give away a new design every week.) They also sometimes have fun survey questions where they crowdsource for their blog. This week's, for example, asked subscribers what they would do if the internet didn't exist.
For example, I can safely share that I listen to a lot of music, and I’m almost fanatic about sound quality. I might listen to an album with poor sound quality once, but I probably won’t go back to it. And to be clear, 95%+ of new recorded music has what I consider poor sound quality (due to an absurd standard of perceived loudness, which takes away natural dynamic range from the sound). That said, I’m not a hi-fidelity sound geek. I’m perfectly happy with my high-end studio monitors—I don’t buy $1,000 power cables, $5,000 CD-players, or $20,000 loudspeakers capable of playing back sounds too high for dogs to hear.
Whenever possible, add a personal element to your emails. Most email tools allow you to enter shortcodes that will be replaced with the recipient’s name when the email is sent out. Emails from Treehouse Co-Founder Ryan are always fun and personal. The subject lines are creative, messages are sent "from" Ryan's email address, and the content is personalized. If you reply to the mail, you'll even get a prompt response from Ryan himself!
You can assess the interests of individual list members by monitoring which pages they land on, and where they go from there. The process is explained by this example from Airbnb. They use click behaviour to ascertain the destination preferences and travel styles of customers and base their follow-up emails on those preference profiles. It's intensely specific, but it gets results!
Location: Businesses that offer local service, such as a lawn service company, obviously need to target local customers, but regional, national, and global companies can also benefit from location-based personalization. Consider running special campaigns for customers in a specified location based on regional events or what’s happening at your local office.
Another way to extend the clicks on your email beyond its shelf life is to prompt your audience to forward the offer. The folks at Litmus found that the most forwarded emails were 13X more likely than the typical email to include “Share With Your Network” calls-to-action. By including forward-to-a-friend (or social sharing links, as we discussed above), you put it in recipients' minds to share.
Are you willing to alienate people who disagree with your opinion? Sure, not everyone who disagrees with you will unsubscribe. But if you can’t take the risk of alienating a large portion of them, it’s better to avoid the topic. The only exception are friendly disagreements. For example, it can be a good idea to show your support for a specific sport team, even if you know many in your audience like another team. As long as they don’t take the sport very seriously, it can be just a fun thing to talk about. I could, for example, tell that I’m more of a dog person (we have two dogs) than a cat person. I have nothing against cats, but I like walking with dogs. I doubt almost any cat person will hold that against me.