All of the email providers number one priority is to ensure their users email boxes stay clean from unwanted and dangerous emails. In order to provide this, there are many processes that evaluate your email and authenticate its authenticity and it is not a fraud. This entire practice is called "Deliverability" which requires subject matter expertise as the algorithms are non-disclosed to the public and many methods are based off experience and common shared knowledge

A bad sender reputation prevents emails from reaching their recipients, costing the company significantly because marketing message are not delivered

There are key components that have to be focused on to maintain a excellent sender reputation including the following:

  • Infrastructure: DKIM, DMARC, SPF, Feedback loops, and proper acquired subscribers (double opt-in)
  • Send volume and cadence: It is similar to a credit card spending habits, this how ISP's can monitor fluctations in your sending patterns which could indicate that you may have been compromised.
  • Engagement: ISPs montior how their subscribers interact with the emails they receive, if an email hasn't been opend in 6+ months that signals to Gmail/Yahoo that you keep sending to people that do not want your messages otherwise they would have opened at least one or two emails if they are interested in what you have to offer.
  • Coding of emails: Hacking attempts happen within emails a lot convincing individuals to click certain links and download things, so that they can gain acess to your machine to use it for ill intent. They would disguise code or add little snippets in hopes that you would act on it. ISPs therefore disable a lot of functionality and require specific protocols and rules that one has to follow not to be negatively impacted.
  • Content: What is inside the email is vital for your reputation. Spammers use specific language that are now being flagged by ISPs. For example using words like viagra, cialis will automatically give your front row tickets to the spam folder and eventually being blocked if you don't fix it.
  • Data Hygiene: It is highly important to ensure that you have the latest and greatest information on your subscribers engagement with your messaging. Subscribers that don't open your emails are frowned upon and can ding your reputation. The idea is that if you provide an email service and a person took the time out to subscribe to your offerings, it is assumed that within a 6 month period that at least 1 email would be opened, if not that would signal no interest or some how that user did not agree to the mailing.

Email deliverability practices will vary from one org to another

Your "Sender Score" is similar to your credit score, which is fluid and each score is custom to the user because they are evaluted by multiple factors such as income, how many accounts, debt to income ratio, how old accounts are, payment history, etc. It can go up and down daily based on what transpired earlier. This is the same with your sender reputation, you have to earn an excellent reputation with each email send. If you know all the requirements and pitfalls you can automate and streamline many of these processes to make it easier to manage.