As a general rule, yes, it does.
A blog is a page on you website that is frequently updated with current information.
It acts as a way of demonstrating to visitors that your site is very much alive and open for business.
Even if you don't need to update the other pages on your website frequently, updating your blog regularly, daily, weekly or even just montly, means a potential customer can see that there is a heart beating within.
But a blog does more than simply show the site is being maintained. It allows the business owner to add part of the missing human touch, the conversational element that, despite its many benefits, the Internet lacks compared with face to face meetings.