Consider the daily life of whomever you’re sending a letter to _how many other things might they have on their mind when they read your letter. Maybe they have a meeting in five minutes. Maybe yours is one of 200 letters they have to wade through. Maybe it’s the end of the day and they’re worn out. Giving them a concrete action to take makes it all the more likely that it will “stick” _ they’ll add it to their todo list or their calendar, they’ll pick up the phone, they’ll check out your website, or they’ll respond.
Similar to business or employment_related correspondence, military correspondence also has set standards for the closing (also called a “valediction”) which one should present before one’s signature. If your company conducts business with the military – or if you are applying for a job in the military – you should be aware that “Very Respectfully” (often abbreviated as “V/R”) is used in written and emailed correspondence between military members.