- Not everyone will have set email up on the phone.
- If a laptop is used it adds more complexity if the email is not set up on the device, (or e.g if Gmail is used via a web browser)
- Not everyone will use the Mail app as default and will need to pick the right app
- There may be multiple emails and additional complexity to pick the right 'from' if there are multiple emails being used.
- It is a test of the SMTP server, not the ability to receive email.
- The email needs to match exactly what is being used to sign up when sending the email. With an email inbox email+label@gmail.com can be used as an example.