[mrtksn]

I keep seeing that argument every single time and keep wondering, isn’t there reason to implement JIT? Something like cost benefits outweigh the resilience risks?

It’s not like people start dying on the streets, simply things are getting expensive and hard to get during disturbances.

Are there calculations demonstrating that JIT the risks of optimization are more harmful than helpful in the long run?

[Spooky23]

JIT is a boogeyman in some cases. Ultimately it doesn’t make sense to stockpile parts most of the time for financial and other reasons. If Intel had a warehouse of 1Gb chips, they would have a disincentive to invest in 10Gb, for example.

The dysfunction is the accounting games that companies are incentivized to keep stuff off of their books. Every company wants to look like a software company and avoid stuff like inventory. Some of this is absurd - many companies don’t “own” property, for example, they lease through entities that are sometimes only nominally separate.

Sometimes companies will outsource processes and fulfillment to layers of other entities, each of which do the same thing. Disruptions cascade - I had one issue last year where a supplier’s supplier had issues getting boxes, and a two week delay there delayed downstream fulfillment by 6 weeks. All because the people who ship the end product couldn’t deliver, and the “principal” outsourced the actual management of the process to a third party. If the principal controlled it, they would have gotten it done, as they were punished severely by the contract penalties. They bet on everything working out ok and lost.

[laumars]

Ironically the biggest two IT companies in the world, Apple and Amazon, are ones that go out of their way to control the entire supply chain.

[Naga]

The problem JIT is solving is that raw materials inventory ties up capital (it costs money), and having warehouses of materials is money sitting that could be used for different purposes (capital expenditures, salaries, dividends, etc). Then, if for some reason the raw materials aren't worthwhile anymore (spoilage, tech change, etc), you've wasted money on something that needs to be disposed of. In theory, the goal would be to have no inventory at all.

JIT is a firm level decision, not a society level. It's up to each firm to decide how much of something they are buying.

[gumby]

JIT assumes a steady state, so squeezes all the buffering out of the system. But buffers are useful.

> It’s not like people start dying on the streets

Well, that’s a good example: there was a huge rise in need for masks and other protective gear about 20 months ago and the supply chain couldn’t handle it. That was why people were encouraged to use makeshift cloth masks, to leave the surgical masks and respirators for medical personnel who had the greatest exposure.

Eliminating buffering cuts cost and can lead to lower prices as well. But at best it merely pushes the buffer elsewhere.

Another way of looking at it: leaving seatbelts out of cars would save money and really, most cars are not involved in accidents so are they really needed? Pass the savings on to the customer!

[mrtksn]

I know the benefits of having a buffer but do we need buffers everywhere? As in your example, wouldn't be much better to have a buffer in the hospitals(or maybe some kind of regional emergency organisations) as a precaution for an outbreak instead of advocating for buffers across the textile industry?

I like the way you put it, JIT simply pushes the buffer elsewhere. However, this seems like a very good thing to have because those who cannot afford running out of something can do a buffer themselves instead of blindly everyone keeps buffering.

[tablespoon]

> I know the benefits of having a buffer but do we need buffers everywhere? As in your example, wouldn't be much better to have a buffer in the hospitals(or maybe some kind of regional emergency organisations) as a precaution for an outbreak instead of advocating for buffers across the textile industry?

The problem with that specific kind of stockpile buffer is that it can become quickly depleted. No mask stockpile would have been sufficient for the COVID pandemic.

From my layman's perspective, you need stockpiles and excess production capacity to weather a supply shock. It's sort of like backup power in a data center: you have UPS batteries (stockpiled power) to fill the gap until the generators (extra production capacity) can come online.

[mhb]

You also need the ability to raise prices when there are shortages in order to encourage buffering. Unfortunately, the people who like anti-price gouging laws appear to prefer shortages and misallocation of goods.

[tablespoon]

> You also need the ability to raise prices when there are shortages in order to encourage buffering.

No, but I can see how someone would some to that conclusion by thinking narrowly in terms of pop free market dogma.

> Unfortunately, the people who like anti-price gouging laws appear to prefer shortages and misallocation of goods.

Price gouging is actually a worse misallocation of goods. It's still a shortage, but it just doesn't hit rich people as hard. If you have food stockpiles to barely feed everyone through winter, it's not a proper allocation to let the market price food so richer people can feast and some poor people starve to death.

Price gouging introduces a lot of (especially short term) inefficiencies as greedy parasites make profit-seeking decisions based on their greed and not social need.

Markets work very well in some contexts, but it's a mistake to think they work best in all contexts. Crisis shortages are not one of the contexts where they work well.

[caylus]

> It's still a shortage, but it just doesn't hit rich people as hard.

It sounds like you're assuming that increases in price don't increase quantity supplied. While this may be true in some contexts (e.g. completely unexpected global crisis), there are many cases in which it does:

- In a local crisis, an increase in price encourages shipping in goods from areas not in crisis. Why would someone take the risk of shipping for the same price they can get elsewhere?

- As the GP mentioned, the ability to raise prices provides an incentive for stockpiling goods. Why would someone incur the expense of maintaining a stockpile in exchange for no benefit in a case where the stockpile is needed?

I'd also argue that it's very unlikely for price increases to render all basic necessities impossible to afford, even for poor people. Consider water - even for someone living in poverty what percent of their budget would you guess is allocated to water? Maybe 5%? So even a doubling of the price of water (for context, price gouging laws typically restrict price increases to around 10%) would only increase that to 10%, leaving plenty of room for them to reallocate not-as-essential parts of their budget. For food perhaps the original percent is higher, but there's much more opportunity to substitute cheaper foods in a crisis situation.

[bsder]

> Well, that’s a good example: there was a huge rise in need for masks and other protective gear about 20 months ago and the supply chain couldn’t handle it.

I'm going to bump you just a little on this because your point is mostly right.

In the US, there were manufacturers ready to add extra shifts for producing masks, but nobody would cut them the check.

The point of JIT is also so that when something goes wrong in inventory you don't get saddled with a bunch of waste. The problem is that means that you need quick, accurate decision making for when the inventory situation does go wrong.

In this instance, all the players who could cut a check for masks were all paralyzed by their systems for various reasons (bidding/disclosure requirements, political ideology, etc.).

[aidenn0]

I don't think anybody actually did the math on this though. It's more like "I get a fat bonus if I decrease inventory without a significant effect to sales over the next 3 quarters" so as long as the near-term risk is worth it, it gets done.

[edit]

There's also the "If I don't implement JIT, I'll get replaced with someone who will" effect in a lot of cases too.

[Guest42]

That’s the impression I get, not so much JIT but rather limiting supply budgets as much as possible. A lot of companies tout Toyota as the pinnacle of manufacturing without realizing that they are not Toyota and there was more to Toyota’s success than JIT.

[unilynx]

Well only a decade ago Moore's law ensured that keeping any amount of stock on CPUs/GPU/memory would cost you a lot of money, as that would depreciate fast. JIT was a good idea until it wasn't

[whatshisface]

The Moore's law argument does not apply to low performance embedded chips which are whatever the engineers want them to be, but must be exactly what the engineers wanted them to be. The chips themselves were often the same between different models of the product, but even though demand for them was a very predictable function of the number of products made, and stable over time (pursuant to the stability of demand for the product), everyone's inventory consisted of whatever was in the box that was being carried from the loading dock to the pick and place machine.

[q-big]

> Well only a decade ago Moore's law ensured that keeping any amount of stock on CPUs/GPU/memory would cost you a lot of money, as that would depreciate fast.

This clearly holded for PC components, but rather not for, say, microcontrollers for conservatively developed products with a much longer service life and/or duration of sell.

Consider, for example, a stock of microcontrollers for an industrial machinery that

* will be used for 20 years by the customers,

* will be sold for the next 10 years,

* after these 10 years, for the remaining lifetime of the machine, the customer will still be able to buy spare parts.

[tablespoon]

> I keep seeing that argument every single time and keep wondering, isn’t there reason to implement JIT? Something like cost benefits outweigh the resilience risks?

Just think about evolution: species specialize for short(er) term benefits, but then conditions change and a lot of those specialists go extinct.

JIT is specializing for an extremely reliable and undisrupted supply chain.

[lisper]

It's a value judgement. You can optimize for the normal case at the cost of disruptions when the unusual happens, or you can optimize for the unusual case at the cost of inefficiency when things are normal. But you can't do both.