Owners have experience in the business, a well designed, nice looking website with fast/responsive pages, reasonable prices on buyers site, fair royalties on sellers side, so everything seems fine but the sales. At the beginning of 2013 they were performing much better than today. So what has changed, what is it that they are not doing today but they did in the past? Is it marketing?
I would say the biggest thing that changed is the google images issue, which has been discussed elsewhere in these forums.
Making it easier to swipe images from google images rather than go to the site where the image is hosted hurt most of the stock agencies to some degree, but I think it took a greater toll on the smaller sites. GL has seen the same sort of drops in sales and been honest about what caused them.