Well this is an interesting article at Gaping Void. Blogs are about words, not images per this theory.
What happened to a picture is worth a thousand words? Darn!
Yes, I do think art sales success is by personal connections, either with the artist or with a trusted art enthusiast (who then generally has the connection with the artist). A really successful art gallery provides the bridge to the artist and the buyer. Art customers usually do want more than just the picture.
So if the premise is sales, most artist’s blogs fail. And if the premise to reach an audience, ditto. No one blog will be found on the internet without some fortuitous notice or concerted marketing effort, no matter how amusing. And if a blog is abandoned quickly, that is probably a sign of failure.
On the other hand, there is my blog. My blog is personal, a diary and a record for myself, but not a private one. It is shared with friends, or anyone who chooses to peruse it. It provides me with a visual history that I love having!
My first site was hacked after about six months, and I lost it all. I felt bereft. Although I probably have all the images I posted there on my computer (and backed up), I did not have the comments or the sequence. I like having that. So I started over, and make backups now. So not a failure, I think :-)