In order to reduce the amount of times you have to update your number of torches (etc), and also to introduce some random uncertainty, some people suggested an alternative method. Instead of putting "10" in the number of torches you have left on your character sheet, you could put "1d8". This means that every time you need a new torch, you roll 1d8.
If the result is anything other than a 1, then you don't have to update your character sheet at all. But if you do roll a 1, you change it from 1d8 to 1d6. And if you roll a 1 on the d6 in the future, it goes to 1d4. And once you roll a 1 on the 1d4, you're out of torches.
Again, the point of this is to reduce the amount of times you have to change the number of torches you have on your character sheet. Also, it introduces tension - you're several levels into the dungeon, and you only have 1d4 torches left; will it be enough?
This is all fine. I like this system. But it does have a small problem, I think.
Let's say you have 1d4 torches left, and you buy 2 "units" of torches to go from 1d4 through 1d6 up to 1d8. Each "unit" (read: die) you buy costs the same. But, and here's the (slight) problem: going from 1d10 to 1d12 is more valuable than going from 1d4 to 1d6, because the 1d12 only has a 1 in 12 chance of depleting (which is good), but the 1d6 has a 1 in 6 chance of depleting (which is worse).
In other words, it always makes sense to buy as many torches as you can (if you ignore encumbrance, I guess), because the last "unit" you buy will be more valuable than the first (read: have a smaller chance of being depleted).
So, one way of changing this would be to flip it around: Having 1d4 torches is the MOST amount of torches, and when you roll a 1, you switch "upwards" to 1d6 instead. Then, when you finally get to 1d12 roll a 1 on that, then you're out of torches.
This doesn't solve the problem of each "unit" of torches you buy is valued differently, but at least then the least valuable ones you buy are the ones you buy last, instead of the ones you buy first. This introduces diminishing returns on buying loads and loads of torches, which has some positive effects. But the problem with this approach is that it's less intuitive ("What? Having 1d12 torches means I have LESS than 1d4? That makes no sense!").
So, what do you think? Personally, I feel like I'm overthinking this and that I should just go with 1d4 being the lowest amount which is more intuitive, and the problem with that which I'm describing above is so small as to be insignificant.
Additionally, I want to abstract this further and say that instead of "torches" in your inventory, it should just say "supplies" which includes torches, arrows, and other similar resources. The point of this would be to reduce clutter on your character sheet.