There is the perception and certainly some anecdotal evidence that there's a correction taking place in the board game market. Publishers are feeling it and stores are certainly feeling it. It's not that there isn't a huge plethora of great games, because there is A HUGE PLETHORA OF GREAT GAMES. Oh dear lord are there an awful lot of great board games right now. The games are great, but there are simply too many. Or in economic terms, there is too much supply for the existing customer demand, with the modern caveat of from me, and at full price.
As retailers, we are always on the look out for great games and we are trained to order deeply when we find them. Otherwise, the game is gone in moments and those with the deepest pockets make the most money. Some would say this is the only way to make money selling board games. You buy deep or you go home. So we buy for the duration. How many titles do we buy? We buy the good ones. How many is not a question we normally ask.
There is no simple mechanism for managing inventory for a department, keeping it in its lane. I use and evangelize the retail tool, Open to Buy. I budget for the entire store with Open to Buy. The complexity of budgeting by department is something better handled by software. That's not to say I won't attempt to make such a spreadsheet, only that it's near impossible to get small hobby retailers to use a basic OTB spreadsheet and most are certainly not going to divide up purchasing by department. That's like preaching pivot tables to cave men (note I don't know how to use pivot tables).
That leaves us where we are now, with many retailers deeply overstocked on product that will never be bought at full price. How deep depends on the other thing I like to preach about, performance metrics. I am certainly one of those retailers beset by fantastic games nobody is buying, but my quarterly inventory performance analysis, usually related to turn rate metrics (or sales per square foot or GMROI), means my problem is a Q4 problem, rather than a 2018 problem. A lot of retailers are using Black Friday to exhaust port stuff I haven't seen in my store for many moons, and it's frankly too late. Good for them, but the crisis could be averted by a regular culling of the herd.
My point in all this is we have tools to keep our stores running smoothly in both the buying (Open to Buy) and inventory management (turn rate analysis). Now all you have to do is thread the needle and master the the rare independent game store skill.... selling. Buy smarter, manage better, sell the hell out of that cardboard.