Just-in-time, often abbreviated JIT, was developed in Japan in the 1990s. Factories, instead of having a large warehouse of parts for their products, ordered just enough parts to keep up with the assembly on the floor. This saved money in two ways: less expensive warehouse space, and less money tied up in parts and supplies.
In the years after 2000, many retail houses and grocery stores followed suit. Wal-Mart is famous for ordering exactly what is bought, to fill the empty spot on the shelves as quickly as possible but little backstock. In groceries, as in factories, JIT means less warehouse space, and less money tied up in products, especially perishable products. The profit margin in supermarket chains is surprisingly small, and they will shave pennies wherever they can find them.
There's a problem with JIT. What if a supply disruption occurs? What if there is a strike, an epidemic, a blizzard or ice storm, a hurricane? A power outage? An oil embargo? Or, most topically today, a sky full of volcanic ash which prevents airliners from flying?
If you haven't seen the news, UK supermarkets are running out of stock on imported perishable produce and cut flowers. In the UK, the markets have been particularly avid for JIT. Most markets have less than three days supply of perishables.
Now, as we know, people in Great Britain won't starve if they can't get baby corn from Thailand, or roses from Kenya, or strawberries from Argentina. But with a relatively large population, and not that much arable land, and especially considering the season, the gaps on the supermarket shelves will be noticeable. Nobody knows how long the Icelandic volcano (I won't try to spell it) will spew out ash. There is the potential of real problems there.
There's an alternative to Just In Time, one which our forefathers and foremothers lived by, which is Just In Case. They understood that life is uncertain. They knew that "unforeseen" weather events are actually common. Emergencies happen at every scale from the individual to the nation.
It was part of the economy of the household to have a stock of foods on hand, to carry them through expected and unexpected challenges. If you didn't put up those apples and plums in the fall, you didn't have any until the next harvest. If you didn't have enough flour and coffee on hand when the snow fell, breakfast was pretty sparse.
With the advanced transportation network of today, we're overconfident, bordering on hubris. How many of us have even the paltry two weeks of food and water in our house that FEMA recommends for emergencies such as pandemics? A serious pandemic could have the stores closed for a couple of months. A truckers' strike could have the stores running out of food and supplies in a few days. A little desperation on the part of the shoppers could clear the shelves in a few hours.
You can apply Just In Time vs Just in Case to more than just food. Just In Time lives paycheck to paycheck. A bill is paid just when it is due. A furlough, a layoff, an illness, and you're behind. Just In Case has economized enough to have some savings stashed away, hopefully enough to carry the family through the emergency.
Just In Time leaves the home at the last possible moment to get to work or an appointment. Just In Case leaves time for traffic jams, a desperately needed stop at the gas station, or the cat dashing out into the street just as you leave the house.
Just In Time hopes that when retirement comes, planned or unplanned, a nice bull market will have made their scanty 401(k) sturdier. Just In Case has put away savings in more than one basket, and is prepared to forgo some luxuries today to avoid poverty tomorrow.
So, take a lesson from volcanic ash, from Snow-mageddon, from ice storms in Missouri, from week-long power outages in New England, from... (you can certainly add to this list from news items in the last couple of years). Be prepared. Just in case, have staple foods on hand, ones you know how to cook, ones the family likes (or tolerates at least). Just in case, have some extra blankets and sweaters. Just in case, have extra drinking water stored. Just in case, have a first-aid kit and know how to use it for common household emergencies. Just in case, have a few cans of chicken soup in the pantry. (If you are sick with a cold or flu, you won't want to run to the store to get it.) Just in case, have some way to cook if the electricity is off for a day or more. Just in case, have at least one phone that doesn't need to be plugged into an electrical outlet, and at least one radio that runs on batteries or by hand crank.
It's a good feeling to have food on hand, to have some simple emergency supplies, to know that you're prepared for the all-too-common unexpected event.