Everyone likes to wax poetic about the million reasons why a business should get into blogging, and why a weblog is the cornerstone of a smart Web site. Heck, even I’m not immune, I’ve been writing – and lecturing – about this for years now.

But sometimes, truth be told, there are businesses that shouldn’t be blogging, and there are people in businesses who shouldn’t be writing entries for the company weblog, and even specific topics that just are not appropriate for a corporate weblog. Let’s have a look, shall we?

First off, let’s agree that the goal of a good business blog is to raise your visibility in your customer community or market segment, to increase your credibility as an expert and to humanize your company and present yourself in the best possible light. Reasonable?

Are you a gardener? You could blog about taking care of gardens, flowers, plants, fertilization, smart techniques for mowing lawns, winterization, etc. A funeral director? Oh, that’s an industry rife with con artists and shady businesses, so talking about funerals and how to ensure that you have the death ceremony you want would be a terrific weblog subject. Maybe you’re the gal who drives the ice cream truck around the neighborhood? Write about children, play, and the changes in our society you can see as you get a unique glimpse into children, parents, and guardians (not to mention children’s manners!)

So, seemingly, there’s not a business you could be in where a blog wouldn’t help you gain visibility and credibility. But there is an assumption in what I’m saying here: that there’s a story and that you can figure out how to tell it online.

Imagine two opticians. One says “I take care of eyes. There’s lots of medical info on eyes out there, so my Web site will be a digital brochure, and that’s good enough for me” while the other says “I get the same questions from every patient, and there’s so much confusing information online, I’m going to try and shed some light on eye care and eye health by writing about it. But not with a newsletter, how 90s!, but with a blog.”

Now, a slight aside: I believe that the future of business is findability, and if your business doesn’t appear when your potential customer looks for you online, you’ll eventually wither and die. Given that, you can guess which optician I think is going to be more successful in 24 months.

Let’s be frank, though. The first optician above should not blog. They aren’t going to be engaged, interesting, or informative, and they’ll find that the exercise of setting up a weblog and having a blank “input box” staring at them each morning will be more than they can handle, and they won’t stick to it and work on their blog for at least six months before they ask “am I getting results?” Better for them not to start at all.

I actually encounter a lot of businesses that have this philosophy, what I call the “let the customer come to me” approach to business. They’ll pay for an 800 number, they’ll print up a newsletter, but the level of their engagement with their market is fairly minimal. Many of them are also hourly professionals — think psychologists, acupuncturists and massage therapists, for example — and their response is “I’m already booked, why would i want more customers?”

If their goal is to fill up their appointment calendar, then they’re right, and they certainly shouldn’t blog or, perhaps, even have a Web site at all.

But what if they could be selling their expertise rather than their hours? What if they could be blogging about their profession and upselling high quality, professional ebooks that cost them time + $500 to produce, and net them $25k annually? That’s a smarter way to look at these professions, isn’t it?

Being completely honest, there are also people who lack coherent writing skills. They may be delightful in person, but put them in front of a computer (or a podcasting mic) and they freeze up, become dreadfully boring, or simply have nothing interesting to say. That’s a real problem, and is one of the rarely mentioned downsides of the entire blogosphere. Put frankly, most bloggers stink as writers. If your company has these sort of communicators, keep ’em far away from your blog! After all, it’s more trouble, more cost and certainly more ineffective to have a boring, dull, tedious blog than to just have a regular old “brochureware” Web site.

Finally, there are specific topics that I believe you shouldn’t blog about, even if you’re the most zealous and enthused of business bloggers. Personnel issues? Customers suing you? Spouse just ran off with someone else? Kids thrown in jail? Have a strong partisan reaction to political news? All of these are topics that should stay far, far away from any sort of business blog. (this isn’t to say that you shouldn’t blog about them, but please, keep it separate. I blog about parenting at The Attachment Parenting Blog, but it’s kept quite separate from my business weblogs The Intuitive Life Business Blog and Ask Dave Taylor, for example)

Some blog experts believe that you should follow the digital version of “let it all hang out”, writing about any and everything that strikes your fancy, but I think they’re wrong. But then again, maybe they aren’t, and maybe I’m wrong!

What do you think?