The machine is priced against the refill it will need

Treat the sections below as a sequence. With consumable-led pricing, getting the early decisions right makes the later ones much easier.

The structure behind the cheap box

Where a device only functions with a consumable the maker controls, the two prices are set together as one commercial decision. The hardware can then be priced near or below cost, because the margin is recovered over years of refills from an owner who is unlikely to switch.

This is a deliberate and entirely legal structure, and it appears in categories from printing to coffee to water filtration to cleaning equipment. It survives because the upfront number is what shoppers compare, while the running cost is spread thinly enough to escape attention. Recognising the structure matters more than judging it, because it tells you which number to compare.

Why the shelf price stops being informative

Two devices with a large gap in purchase price can end up costing similar amounts over their lives once consumables are counted. They can also end up in the opposite order, with the expensive machine cheaper to own, which is the whole point of doing the arithmetic. The comparable figure is cost per use: the price of the consumable divided by how many uses it delivers, plus the hardware spread across its expected life.

Manufacturers rarely present that number, and where they do the assumed usage is often generous. You can build it yourself from the pack price and the stated yield, which takes a couple of minutes and lasts for years.

What lock-in is actually made of

Lock-in can be physical, where the cartridge shape fits nothing else, or contractual, or maintained through authentication built into the device. It can also be purely practical: once you own a stock of accessories for one system, switching means writing those off. The strength of the lock determines how much freedom the maker has to move consumable prices after you have bought in.

Third-party alternatives exist in many categories and change the arithmetic considerably, though compatibility and warranty questions vary by product and by country. Before buying into any system, it is worth knowing whether an independent supply exists at all.

The price you agree to later

The purchase price is fixed on the day you pay; the consumable price is not, and it can drift upward across the years you own the device. Nothing obliges a manufacturer to hold a refill price, and a large installed base of owners is precisely the condition under which raising it is safe.

Pack sizes can change too, which alters cost per use without altering the price on the shelf, so the pack is worth checking as well as the price. For a long-lived device, assume the running cost will rise somewhat and build that into the comparison rather than assuming today's figure holds.

A system with several independent suppliers is structurally more stable in price than one with a single source.

Subscriptions built on the same idea

Many consumable systems now arrive as subscriptions, which smooths the cost and makes the total harder to see. A subscription that adjusts to your usage can genuinely reduce waste, and one that ships on a fixed schedule can quietly accumulate stock you do not need. The relevant check is whether the plan price per unit beats buying the same consumable outright, which is a single division.

Run the arithmetic and watch the cancellation terms as carefully as the price, because a low per-unit rate tied to a long commitment is a different product. None of this is advice about your finances, only arithmetic you can do with the numbers in front of you.

Doing the sum before you buy

Write down the pack price, the stated yield, and how often you realistically expect to use the device in a normal month. Multiply out to a yearly running cost, then add the purchase price divided by the number of years you expect to keep it.

Run the arithmetic and compare that combined figure across candidates rather than comparing the tags, and the ranking often changes. Check whether independent consumables exist and what they cost, since that sets a ceiling on future increases. The exercise takes minutes and applies for as long as you own the thing, which is a better return than any single discount.

The takeaway

When something needs refills, the tag is a deposit and cost per use is the price.

Decide what you would pay before you look at what they are asking.