I'm a self defence instructor and as such I like to get my hands on every good instructional material available.

Note I emphasize the 'good' in that last sentence.

And, in order to ensure I get only the good material, I read and watch as much as I can in order to find out what's out there.

When I say read, I mean everything- sales letters, articles, and videos - you name it.

You see, it's what I'm interested in, and so I'll make the time to glean as much information as possible from the internet and any other sources I can get my hands on.

I'll even scrutinize every last letter of any sales letter I receive through the post.

I don't get tired of reading about the martial arts and any related matters.

If by doing as much research as possible I get the best training material available, then my time has been used constructively and has been of benefit.

If, on the other hand, I receive a sales letter through my door extolling the virtues of turkey farming down in the West Country I'll discard it without giving it a second glance.

That sales letter could be one page long, or even a paragraph, it won't make a difference.

Why?

Because I have no interest in turkey farming down in the West Country, or any other part of the country for that matter.

And here is what makes the difference between long copy and short...

... It comes down to one single point - is it something I want to know more about?

If the subject is something I'm not interested in, why should I even bother to waste my time reading it?

If it is something I want to know more about, sure I'll read it.

However...

...If I already know about a particular book or DVD set I want to buy then it's useless trying to get me to read a twenty page sales letter.

In such a case, all I'll want to know is how to pay for it and just get the darned thing, so a long sales letter would be as waste of time.

You see if the niche is so small it's likely I'll know everything about it anyway, why bother trying to convince me to buy it?

Say, for example, I get a sales letter through advertising a male parrotlet (something my niece is looking for as a mate to the female one she already has) I won't need to be convinced any further.

Why?

Because parrotlets are difficult to come by and aren't available everywhere.

I won't read the sales letter, I'll just send of for the necessary information, or send the brochure to my niece who I know will be interested.

So, the length of your sales letter does depend on what it is you're advertising and how much information is necessary to persuade your prospects to desire your product.

Don't just assume you know what your reader wants, find out.

And the best way to find out is through research.

Without research you could be just wasting your time.