The ideal number of times you should be emailing your customers is at least once a month or once a week. In order to keep them reminded of the fact that you have products that might interest them.
When you avoid sending customers emails, you are not using the resource of generating additional revenue through email marketing.
One thing to keep in mind is that if you have enough content of value, you can even send up to 3 or 4 emails a week. It is key to remember that you should be sending emails, only when you are confident that your content is great and can be promoted enough to ensure that your customers take the actions you want them to.
Another aspect when it comes to sending in multiple emails, you should edge on the side of caution, as sending an overwhelming amount of emails might persuade your customers to unsubscribe rather than implement the actions you want them to take.
