It’s estimated that by 2017, around 206 billion emails will be sent and received each day. And even though 69.7% of Internet users prefer to communicate with businesses through email, a business still needs to have a winning email marketing campaign plan if they want their emails to be read.

Time and time again, the data proves that email marketing continues to provide a high ROI for businesses. So why do email-marketing campaigns fail and how can your business keep yours from flopping? Here’s six reasons why email marketing campaigns might fail to receive the ROI you expect.

1) IT SMELLED LIKE SPAM

Nobody likes the cat food smell or taste of real SPAM, and email spam is just as revolting. 69% report email as spam solely based on the email subject line. If you’re saying, “but wait, my company’s email isn’t spam, so why should I care about this?” there’s something you should know: to an email service provider and to your users, you are viewed as an anonymous source. If your company’s email headline or body copy smells fishy, an email service provider could flag it as spam. Even if it doesn’t end up in the spam folder, users can also flag it if it smells anything like spam. If it happens too frequently, you could get blacklisted and be unable to reach your audience entirely.

The solution: A few pointers — never use deceptive headers, make sure you haven’t been blacklisted and avoid using all caps. For more tips, click here.

2) IT WASN’T OPTIMIZED FOR MOBILE

Recent reports have discovered that 66% of all email in the United States is opened and read on smartphones or tablets. Still not motivated to go mobile? Maybe this will persuade you: Another 2015 study from BlueHornet found that 80% of users delete an email that isn’t mobile-friendly, while 30% unsubscribe from the email list entirely.

The solution: Use templates that are responsive and will allow for flexibility in your email design. Most email marketing platforms, like MailChimp and Constant Contact, offer a variety of mobile templates to choose from.

3) IT DIDN’T GET PERSONAL

Building relationships doesn’t happen overnight and it requires a certain element of trust and relevancy. One of the easiest ways to make an email marketing campaign more effective is to make it personal.

The solution: Address the reader by name and show them how your email can solve whatever problems they might be facing. Always, always, always customize email messaging to the appropriate audience.

4) THE CALL TO ACTION WAS UNCLEAR

Getting readers to open your email is important, but getting them to click through and convert is the main goal. Without a call to action (CTA), there is little or no point to an email marketing campaign. Your CTA should be the primary focus of your email and should stand out amid the body copy. It should also tell readers what action you want them to take next and guide them to that next step.

The solution: Make sure CTAs are visually distinctive and use copy that indicates a clear action for the user to take. For example: “Download,” “Book Now,” “Learn More,” “Request a Demo,” etc.

5) THE VALUE PROPOSITION WAS MISSING

Value propositions have a major effect on an email campaign’s click-through rate. This is the part of the email that describes the benefits readers can receive from using a particular product or service. In essence, a good value proposition hands your company’s offer to readers on a silver platter and tells them why they should care about and act on it.

Here’s an example of a value proposition from a new product announcement email from King Arthur Flour:

The value proposition is simple: King Arthur Flour has a new product that can make incredibly delicious looking cookies. Print the coupon and you can save on “your new favorite ingredient.” The email does its job because it tells readers what the new product is (almond flour) and how they can benefit from it (save money on delicious product).

6) IT WAS AN EMAIL

Even though email marketing has one of the largest ROIs for businesses in terms of digital marketing efforts, the reality is that not every audience responds well to email. Monitor your results and if you need to, don’t be afraid to adjust your strategy. Try targeting unsuccessful email audiences on social media and see what channel they respond best to. No two leads are created equal.