Clients often want to start a blog. It's seems to be what all the basic SEO courses push.
My response is generally:Finish your evergreen content first
. And make it the best you can. By that I'm talking about the core pages of the website like the about us page, the why buy from us page, the contact page. Pages that are always at a high level of the website and are read by most of your visitors. They are the ones that sell your business, not a blog.
Once you have done that, then you can think about a blog.
I've seen enough businesses with one posts blogs to make me realise that a business owner's enthusiasm dies rapidly. If they are not dedicated to the blog idea, then they should run away and spend the little time you would have put into the blog doing something more constructive for the business. Like door knocking.
For a blog to work, a lot of effort has to be put into it. You have to become an authority in your field. It has to make visitors respect you, and want to follow what you say. Regurgitating what many others have already said just doesn't cut it. You have to stand out and get remembered. I often spend a whole day putting together an article, and I don't think they are as good as they could be.
This whiteboard friday explains things very well. In fact I love what +Rand Fishkin
calls the minimum bar:"As good as the best in the SERP"
That is, you need to be at least as good as the best article you have ever read on the subject, but ideally far better.
Are you up to the challenge?