Subscriber SM, a successful freelance copywriter, writes:

"A potential client contacted me. He wants me to guarantee results.

"I told him no copywriter can guarantee an increase in conversion ... although there's a strong chance if there's a budget for ample testing -- and the client has globs of traffic.

"One of these days, I’d love for you to write a blog/email about potential clients who scream for a guarantee. I think all copywriters would love to hear your thoughts based on your experience.

"On the one hand I have to say, 'I'm going to help you get results' but there are too many variables to guarantee a lift in conversion."

My answer is simple, and I include it in all my client agreements for every copywriting project I take on:

"There are many factors in your marketing -- product, market, price, list, demand, consumer preferences, competition, major events -- that Bob cannot control. Therefore, he does not promise and cannot guarantee specific results."

The most important thing to note is that the client and I discuss -- and the client agrees to -- this term in advance.

Now, let's drill down deeper.

To begin with, SM is right: You cannot promise a specific result -- e.g., 7% conversion on your landing page.

If you could, it would mean every promotion you write is a guaranteed winner -- and no copywriter has that ability.

If I could in fact write a winner every time out, I would own my own island by now ... and Bill Gates would be my houseboy while George Soros washed my Rolls in the driveway.

So you can't promise and deliver a given result, either specific (e.g., 5% response on a postcard mailing) or general (e.g., your promotion will make money for the client).

What you CAN guarantee or promise is that if your copy does not deliver a certain level of response, you will compensate the client in some way.

That compensation is either giving back part of your fee (or not charging for any balance due) or redoing the work at no charge.

My contract promises neither. It clearly states that I am paid when the work is done, regardless of sales or response produced by the copy.

And that works both ways: If the package generates a million in sales instead of the forecast $100,000, the client keeps all the money and I do not get a cut.

The reason, as the clause I quoted from my contract states, is that there are many factors in a client's marketing -- product, market, price, list, traffic, demand, consumer preferences, competition, major events -- that we copywriters have no control over.

Example: I arranged for my client SH to distribute an HTML e-mail, offering a free report I wrote for him, to an opt-in e-list of a few thousand names, provided by a reputable list broker for around $1,500.

A few days before the scheduled e-blast, SH told me he had found another list source, one I have never heard of, who would distribute his e-mail to a few thousand names for $250.

Though I explained to SH the likelihood was that this cheap list was garbage, he decided to go against my advice and use it.

It bombed. SH has, I hope, learned a lesson on how a factor other than copy can determine the outcome of a promotion. And you can see why copy alone cannot assure results.

Here's another problem with guaranteeing results: What if the client changes some of the copy in a way that ruins its effectiveness, and then tells you that "your" copy didn't work?

If the copy was changed, how can the copywriter be held accountable for what the client did behind his back and without his approval or involvement?

In my opinion, the only way one could even remotely consider offering a guarantee is to insist the client run the promotion exactly as you wrote it, without changing a word unless the copywriter makes and approves any change.

And I have yet to meet the client who will adhere to that if, when he reads your draft, it is not 100% to his liking.