I'll tell you they're only half right.
Yes, each email you send must be high quality (which is where you provide both value and entertainment to your email list). But it shouldn't be a case of quality over quantity. Instead, you should be combining quality with quantity.
The method I recommend (and what other successful email marketers such as Ben Settle and Paul Mort recommend) is to send an email to your list every single day of the week, fifty-two weeks a year. No exceptions.
You see, as long as your emails follow the "value + entertainment" formula, there's no such thing as sending "too many" emails.
Of course, if your emails are boring, then people will get annoyed with you sending daily emails. They'll then unsubscribe from your list or even report you for spam. But then again, if you were sending boring emails, your email list would get annoyed with you emailing them just once a month anyway.
So always remember this: When it comes to sending emails, there's no such thing as too often... Only too boring.
So just how do you entertain your email list?
Do I mean you have to be a comedian?
Absolutely not. I mean, you can be if you're a naturally funny person. But if you're not, don't force it. Plus remember, buying and selling is a serious business. People want to buy from someone they respect; they don't want to buy from a "clown".
Instead, you should entertain your email list by telling stories. Specifically, stories which resonate with your market and then persuade them to buy from you.
The best sales people in history have all been great storytellers.
Make sure you learn how to be one, too.