Sent an email application to somewhere and was expecting a reply from (the somewhere).
My application mail was sent via @gmail , waited several weeks for the reply, checked spam folder over n over.... found nothing. Luckily for me I have the @yahoo.com version of that same email address. Wasn't using it that much (I hardly check the mails there).
Few days to the period given for all applicants to confirm they'll be available for the event.
Didn't know what prompted me to check the yahoo version of the mail....Bam!..... It was there, I found the mail I was expecting in my @gmail inside my @yahoo
How?
The return mail address used by the organization was manually compiled, and the mail sent to my @yahoo(.)com instead of @gmail(.)com.
Want an error!!!!

My advice: If you are creating a formal email address for yourself, try as much as possible to see if you can create both yahoo & gmail version of it. It may be useful to you someday.
Peace ✌