Short answer: To the one who acts like they want it.
Many artists have their work represented by multiple galleries. I currently have work in two different galleries. This is a good thing, but sometimes it can be difficult to decide where to send a painting. Sometimes a gallery is having a particular show that they want you to participate in. In that case, the decision is easy. You make a painting for that show, and send it to that gallery. But, as is often the case for me, I make a painting I want to make, and then have to decide to which gallery it goes.
There are logistic considerations. One gallery I have to ship to, one I don't. In regards to the painting in question, packing and shipping cost is especially important. This painting is on the large side. Advantage: local gallery.
I also think about which gallery has an audience that might respond to the subject matter of the painting. For example, I'd send my Cowboy paintings to my gallery in Colorado, and my Clam Chowder paintings to my gallery in New England. For this painting, I think both galleries would have an interested audience.
Next, which gallery do I need to feed at this time? Meaning, how long has it been since I last sent them a painting? The gallery I have to ship to is hungry. But, they are also the gallery I have to ship to. Again, I'd like to avoid that upfront cost.
What to do, what to do?
Well, I've made up my mind. It came down to this: One gallery reached out to me to say they like the painting, and hope I send it to them. And, one gallery didn't. So, I'm going to ship the painting. I will pay the cost of packing and shipping, and suffer the anxiety of placing my painting in the care of a pimply-faced teenager at Fed-Ex. Why? Because, sometimes I spend months working on a painting, and it's kind of nice to feel that my gallery appreciates that. Frankly, most galleries have no idea what goes in to making paintings, and don't care. It's just a commodity to them, a piece of inventory.
As long as artists need galleries (and I think we still do), we have to deal with galleries who are enthusiastic about our work. Take a look at the roster of artists on some gallery websites. They're endless. I counted 140 artists on the roster of one gallery where I used to show. With that many artitsts, it's easy to get lost. And, can you really expect that gallery to give attention to 140 different artists? True, it's our job to distinguish ourselves, but there's only so much wall space.
So, to have a gallery express excitement about my work means something. It, hopefully, means that they will do more to expose my work. They will be proud to associate the work with their gallery. Bottom line, they will probably put more energy into selling the painting. And, that's what it all comes down to: Selling the painting.