3 Matching Annotations
  1. May 2021
    1. They're less likely to go into the "Promotions" tab in Gmail (used by ~16% of all email users), for the same reasons above. From my testing, the plain emails typically end up in the Updates tab and some times even in the primary tab. Of course, the text in the email also affects this.
    2. You can use a free spam checker to validate this by testing plain and designed emails.