Email marketing is marketing through sending emails. These can be newsletters, campaigns, automatically triggered and also personally sent emails.

What Is Easy To Get Wrong

• Not starting with requirements when choosing an email marketing software.
• Thinking that more opens and clicks automatically means better results.
• Not segmenting customers and messages by their user state in the activation funnel.
• Not moving events (that trigger the emails) to the back-end for better reliability.
• Integrating with all the marketing tools separately.
• Not cleaning out email lists for better deliverability.

What Is Spam?

Spam has two definitions:

• according to law, it's unsolicited email (commercial bulk email that you don't have permission to send)
• according to recipients it's mostly email that's not relevant (even though it might be legal)

Spam laws vary a lot from country to country but the simplest rule to keep in mind is that sending bulk email requires previous permission from the recipient. Unless it's transactional email (e.g. when a customer already has a business relationship with you and when the email is part of the service you are providing - such as an invoice or shipping notification).

Types of Emails

Emails can be divided as follows:

1. personal emails - 1-on-1 emails sent out from Gmail, for example;
2. bulk emails (mass emails) - emails (such as newsletters and campaigns) sent out to a large group of people using special software;
3. triggered emails - emails that are being sent out automatically based on predefined triggers (such as an event, attribute change, time) using special software;
1. triggered marketing emails - emails that are sent out mainly for marketing purposes and from which the subscriber can opt out;
2. triggered transactional emails - emails that are essential for the transaction (invoices, password resets, reminders, etc), the recipients can't usually opt out from those emails (unless they opt out from the service itself).

Note that both bulk and triggered emails can also consist of several emails (called a flow or a drip campaign) not just one.

How Is It Measured?

Email tools provide all kinds of metrics that are mostly related to email opens, clicks, and unsubscribes. While these may sometimes be helpful as leading indicators (or in rare cases as the main metrics if, for example, your product is a paid newsletter), they don't really tell you anything of importance. It's very easy to manipulate people to open more emails with spammy subject lines.

Instead, measure the success of email marketing as part of activation. This usually means that you want to start sending events to email marketing tools to know whether a given email resulted in someone completing a set-up moment, a-ha moment, or improved their retention (note that only those events should count for retention that provide actual value to the user).