I have a pretty simple formula with games to know if they will devalue quickly.
Mid to high third party western releases tend to be fastest to drop from $60. For example just recently I got Rise of Tomb Raider on PS4 for $25 just a few months after it released. I knew this was going to happen the second it was announced so I waited for the inevitable sale. I fully expect Mass Effect Andromeda to drop quickly. I got Mass Effect 2 & 3 for $10 each a year after release.
Meanwhile my enjoyment of niche Japanese games is bit of a crap shoot, sometimes they clearance them out, sometimes they hold or even increase in price. Been burned both ways.