A large luxury saloon typically loses a greater proportion of its value in its early years than a modest hatchback. The reason lies in who buys such a car second-hand and what it costs them to keep.
Where the first-owner premium goes
Much of a luxury car's price buys things that only exist at the point of sale. Specification choices, delivery experience and the status of a new registration all have value to the first owner and none to the second.
Optional equipment illustrates this most clearly. Expensive options add heavily to the invoice and add comparatively little to the used valuation.
What remains after that premium falls away is a large, complex vehicle competing against newer alternatives at a similar price.
Why running costs do not fall with the price
Servicing, tyres, brakes and consumables are sized to the car as engineered, not to what it is currently worth. Large wheels need large tyres whether the car cost a great deal or has since become cheap.
Insurance follows repair cost rather than market value, and a body panel with complex construction is expensive to replace regardless of the car's age.
A used buyer therefore faces a bill sized for the original vehicle, and that expectation is priced into what they are willing to pay.
How complexity compounds the effect
Luxury cars introduce technology first, which means air suspension, active systems and dense electronics arrive here before they reach mainstream models.
Each of those systems is another component that can fail outside warranty, and several of them are expensive enough that a single repair can approach the value of an older example.
Buyers discount for that risk, and the discount grows as the car passes out of manufacturer cover.
Why supply arrives in waves
A high proportion of luxury cars are leased or financed over similar terms, so large numbers return to the market at roughly the same age and mileage.
That concentrated supply meets a much smaller pool of buyers than exists for ordinary family cars, and the price adjusts to clear it.
Fleet and lease returns also tend to share specification, which removes the scarcity that might otherwise support values.
Which cars resist the pattern
Depreciation is not uniform across the segment. Models built in genuinely limited numbers, or with a specification that later becomes unavailable, hold value far better.
Mechanical simplicity helps as well, which is part of why some older analogue performance cars have recovered in value while their electronically dense contemporaries have not.
The pattern is consistent: what depreciates is complexity sold at a premium, and what survives is scarcity that cannot be reproduced later.