A lot of this makes sense for current day releases where the writing is on the wall basically, for said limited production titles. What confuses me more, are the classic games (and games in general) which weren't intentionally limited, but also not massively produced. Some games that fall into this sector, become basically worthless. Others, end up becoming a gold mine. Some will sit at deflated prices for a long period of time, then suddenly see a big rise in value out of seemingly nowhere.
Example, I was shopping Genesis games. One of the lesser known, but still desirable titles is Chakan (which I still do not own). That game can be had for a really low price, even complete. It has been cheap for years and years. Will it stay cheap? Who knows? It definitely seems like a game most Genesis collectors would like to own. Then, I later come across games like Alisia Dragoon and Shadowrun. According to PriceCharting, those games have seen a steady increase more than doubling value since about 2009 to present day. Can you believe people were buying Alisia Dragoon carts at $5 on eBay a few years back? Couldn't happen today. If I had been really aware of these games beforehand, I would have grabbed a copy when they were still dirt cheap. Same situation with SNES, NES, Master System, etc.
Those are the types of heads up I'd love to have concerning the classic platforms. Games that weren't meant to be rare, but could still go either way as far as value. It's difficult to say what makes this happen or not happen with Genesis games, or NES, or PS1 games (any classic platform). One year they're a total bargain, a few years later the price is starting to gouge wallets. So I'd love to know which games are still a bargain that might not stay that way.
Many older games have or are in the process of showing their popularity and peak values just because they've been around for a while and people that may have not known about them now do. Especially Atari, NES, SNES and Genesis games are well known enough at this point by the collecting community where you will likely see little fluctuation, especially upwards in value. Currently systems released during the 5th generation (N64 and PS1, Saturn has been pretty steady for a while) are beginning to come into their own with more obscure/rare titles coming into the light and collectors driving the values up. Probably the oldest system that still has some growth potential in terms of current values and potential future value increased are 6th gen games, excluding the Dreamcast to a certain extent. There are a lot of PS2, Gamecube and XBOX games that are still fairly under the radar because collecting for them has just started to increase. I'd start looking there honestly because unfortunately the NES, SNES and Genesis hidden gems boat departed and arrived to the masses a long time ago.