There's a raging battle going on for the attention of anyone who has an email inbox.

Email is the weapon du jour for online marketers. Why invest hundreds of thousands of dollars in TV ads when you can reach millions of email inboxes for just a fraction of the price? Or so the current thinking goes.

The trouble is, the more emails people receive, the less attention they pay to each individual message.

To stand out from the crowd, online marketers are going to great lengths in order to attract the attention of their audience.

The argument goes something like this:

"If I shout louder and more frequently, the customer will hear me above the din."

Well, that's true. They may hear you. But how will they react to all that noise? Will they be happy? Or will they greet your loud and frequent appearances in their inbox with a collective cry of, "Shut up and leave me alone!"

Here are some of the ways in which email marketers are asking for too much attention from their prospects and customers.

(This is about promotional emails, not about online newsletters. That's a whole different discussion.)

Attention Hog #1: Promotional emails that are too long.

Some promotional emails take an awfully long time to get to the point. Keeping in mind that the recipient is probably getting more emails than he or she wants, don't make them scroll down a screen or two before you let them know what you're trying to say.

Part of getting this right is taking a very disciplined look at the purpose of your emails. How long does it really take to get the message across?

IQVC does a great job of staying focused with their 'QVC's Today's Special Value' emails. They pitch one product at a great price and do it on one screen. Their purpose is to move that product on that day - and that's all they attempt to do.

A lot of companies are a lot less focused and produce long, meandering emails that go on and on and on.

As a result, they ask their readers for a great deal of attention and give them very little in return.

Attention Hog #2: Emails that attempt to do too much.

The other great thing about the iQVC email is that they stay focused on one, single task.

A recent email I received from a Canadian electronics retailer opened with a chatty introduction, then showed me six items I could buy and then added a few more screens of 'computer lingo' definitions.

It was all pretty good stuff. But it was too much and too varied for that single email. Let me subscribe to the chatty stuff (better suited to a newsletter). Let me subscribe separately if I want just the product pitches. And let me subscribe separately again if I want those useful definitions. But the chances of my wanting all those three elements all at once, in the same, long email are pretty remote.

You've asked me to wade through stuff I don't want in order to find the stuff I do want - and you've hogged my attention for longer than was necessary.

Attention Hog #3: Too many emails.

Some marketers argue that frequency is the key to online email marketing. They want to send out promotional emails to their list as frequently as possible.

Yes, there is some sense to this. Traditional marketing wisdom will tell you that to stay 'top of mind', to maintain sufficient 'mind share', you need frequency.

That may be true within a conventional, offline marketing environment. But the online environment is different. While the public may grudgingly accept thousands of messages bombarding them each day through traditional media like TV, radio, billboards and newspapers - people are a great deal more sensitive to the quantity of commercial messages they receive by email.

Offline math does not apply online in this case. Frequency through email can quickly give you a reputation as a time-hog. And once someone has skipped one or two of your messages, it is very easy to slip into the habit of ignoring all future emails from your company.

Attention Hog #4: Emails that are poorly targeted.

Online marketers have all the technology they need in order to segment their lists and ensure that each segment receives messages that are timely, targeted and relevant.

But all too often, marketers online simply carpet bomb their audiences with any and every offer. Why? Because they can. Because it's cheap. The cost of a traditional direct mail piece is high, but the cost of an email is very low. So why bother with targeting when you can reach the whole list for about the same price?

The trouble with that thinking is that you end up sending your customers information that really doesn't interest them for most of the time.

And when you do that, your audience will soon come to recognize you as a purveyor of junk. And they'll ignore you.

Attention Hog #5: Emails that are badly written.

Reading text that is well written is so much easier.

Kick out all that corporate speak. Cut out the jargon. Get rid of the hyperbole.

Write clearly, simply and respectfully.

Poor writing skills are a huge barrier to capturing and holding people's attention. So pay some attention to the copy in your emails. Make sure your writers have the training, skills and aptitude to do a great job.

An email inbox is a very personal space. It's where you finally get to talk to your customer on a one-to-one basis. But you can't get personal if your emails read as if they were written by the folks at 'Dull and Boring Emails R Us'.

Ask for less and receive more.

In a world of increasingly busy email inboxes, the best advice may be to ask a lot less of your customers.

Target your emails more carefully. Keep them more focused. Get to the point quickly and make the value of your offer jump out. And make sure the writing is of a high quality.

In other words, if you are respectful of your readers' time, they will reward you by giving you more of their attention.