On 20 November 2024 the Ministry of Defence told the House of Commons that six groups of capability would be taken out of service, and that the decisions were set to save the department up to £150 million over two years and up to £500 million over five. The accounts for the year in which those decisions were taken record the same retirements as losses of £1,455 million. Neither number is wrong, and neither corrects the other. One is expenditure expected not to be incurred in the years ahead; the other is value already committed that will not now deliver the use it was bought for. They are measurements of different objects taken from different ends of the same decision, and no arithmetic connects them. What lies between them is a question that the two figures cannot settle and that public debate about defence retirements routinely treats as settled: whether removing a capability from the force structure actually frees money that can be spent on a different one. That question is not about accounting. It is about what the department is still legally required to pay after the announcement, what it must spend to get out, what it receives when it sells, and whether what remains can lawfully be redirected.