Despite recommendations from almost everyone, including actual industry professionals, I was initially resistant to the idea of a blog about my art and its processes as, rather selfishly, it felt like another source of congestion in my already bloated agenda, but I've come to realise in the last few months that it kills one major bird and a couple smaller ones to boot, for both the art and the artist alike, and all with one stone.
Primarily, every artist of all levels, amateur and professional alike, appreciates insight into how other artists work. Not only does it allow them to pick up new tips and tricks for their own art, but it brings their personal struggles into perspective when they watch a respected industry titan wrestle with their work. For example, I remember when I was in the early stages of my "training"* and was feeling the full brunt of the frustration that comes with constant mistakes and ugly sketchbook pages, and what brought me comfort and the drive to continue at that time was watching a Jim Lee video where he drew, I think, Harley Quinn, making numerous mistakes along the way but ending with a piece of the astounding quality for which Lee is known. It was a bit of an awakening for me because it gave me perspective on the creative process itself: it simply isn't always plain sailing, no matter who you are. The point is to keep going and not let those issues drag you down, because the end result can still be great.
Anyway, the point I'm making is that a blog allows your audience, be them fans, fellow artists or potential clients, a view into how you work, and that can make all the difference to the kind of following you build. If another artist can learn from you, they'll follow you; if a potential client can see the thinking behind your work, you might be right for their project. It all adds up.
To a lesser but still important extent, blogging is also therapy. Not in any official capacity, of course, but detailing your process in words and pictures rather than just living it allows you to view it from a different, more constructive angle. In the same way psychotherapy helps you understand yourself by talking about your life, experiences and feelings, you can better understand your art when you deconstruct it in words. All in all, the greatest impetus for change is self-awareness.
Finally, and hopefully less pseudo-intellectually, blogging is about communication and community - fundamental topics for any artist. Art as a career is a bit of a solitary one at times, so finding a connection with like-minded people can prove indispensable not only in maintaining one's sanity, but in keeping the creative juices flowing. Everyone has some useful insight on something, and who knows what could inspire you!
* Besides primary school, I've never taken an official art class in my life, but I have worked through various online video courses on anatomy and such to boost my understanding of form. The rest is just persistence. Oh God, the persistence.