When scrolling through the list of emails in my Inbox (sometimes also my Sent box) an unwanted ad opens up between my emails, and I have to click its 'X' and close it.
I find such ads very intrusive ! And by inserting them right amongst my email list, you are being fundamentally rude, - don't you realise ?
Please keep ads where I can ignore them if I wish to. Don't shove them right up my nose !