I’m a game developer and honestly, you are kind of right. It makes the game more fun to be able to haul around things infinitely. A lot of game developers put in cheats specifically so they can either just spawn what they need or carry everything or both. That said, it also ruins the game incredibly well after 2 minutes of you dicking around and having fun with every item without issue.

Overall the basic issue is twofold. One, if you let the player carry everything, then some players are going to look and dig through levels to find everything. Two, Some players won’t do this so you need to stock your levels with enough obvious items to keep the players who don’t explore stocked enough to keep playing. If you do that then the items the exploration players are looking for are just either overpowering them or not giving them any benefits like collectibles. There is a middle ground to this and make exploration reward items different playstyles. Like in Deus Ex, a lot of exploration bonus items are stealth based. Meaning if you want to do a stealth playthrough you’ll be exploring a lot and thus you’ll find less ammo which is on guards or in the middle of guarded areas and you’ll find more hack tools and lockpicks.

So problem solved right? But wait… Deus Ex’s inventory is… exactly like REs. Why? Because the issue above was the basic issue of why to even include inventory. Now we bring in what it adds to the game. Player choice and agency. As the player, you get to pick your own path. In any game with an inventory, you are going to get to pick which things you keep and which you don’t. This means you have to actively make choices according to your playstyle. In Deus Ex the question boils down to, do you take the big fuck off GEP gun or do you keep your inventory lean for lockpicks, pistols, SMGs, shotguns, and assault rifles so you can use whatever ammo you come across. In the first Deus Ex, ammo is very scarce. Thus having room for ammo and the tools to use it is very important. a GEP gun only really works on 4-6 enemies and the ammo is huge as well as the gun. Taking up around a third of the inventory, maybe more, depending on if you get inventory upgrades. This is an active playstyle choice.

Some games are simply built around inventory management, likewise, some games are built around unlimited inventory. The latest Hitman (2016-2021) series allows unlimited inventory and you can certainly build around it. The issue with Hitman is that you lose all of your inventory every time the mission ends then you can only bring select things into a mission to keep your inventory slim. It still rewards the player for exploration because now you know another path through the mission which potentially gets you another item or in a place you didn’t know you could get without the right outfit. Because the missions are replayable the information you gain in one playthrough helps the next. Knowledge of that item existing in that location is enough of a reward.

@Pseu@beehaw.org mentioned that survival games need inventory management. I pose they don’t. Crashlands is a survival game without inventory management and doesn’t even have an inventory screen for better or worse. Inventory management, as far as I am aware, isn’t a requirement of any genre. If it is then someone out there is going to try to make a game to remove it. There are also games that are solely inventory management like Save Room - Organization Puzzle. There are types of people who like inventory management and those who don’t.

Thanks for coming to my ted talk! I hope this was helpful and interesting.

If you have infinite inventory space, then you need a way to navigate through infinite items. Towards the end of the game, a player could easily have nearly every item in the game. For some games, that would be fine, but for many, that would make the list of items prohibitively long. Filtering and searching would help, but if you’re looking for an item that you forgot the name of, a search doesn’t necessarily do much.

Then there’s balance reasons. Some games use their inventory system to limit the player, making sure they don’t start a level with enough health potions and grenades to cheese every fight.

In survival games, a finite inventory sets the gameplay loop: you go exploring/mining and then return to base, drop off your stuff and head out again. It makes your base valuable, if only because that’s where you keep most of your resources and moving would be hard. It also gives the player a break from one task. I played a Minecraft mod that gave me an effectively infinite inventory. I went mining for so long that it started to feel like an awful slog. Because my mine shafts went on too long, getting back was itself a hassle. When I reverted back to a more typical inventory size, I could feel how a full inventory breaks up the grind and prevents mining from getting out of hand.

You don’t like it when their 4 and 8 are dirt and gravel respectively while they embark on their megaproject that uses neither dirt nor gravel?