The more people travel by train, the worse the experience becomes for those who catch the train to work, shop or play.
In other words, success in convincing more people to leave the car at home is affecting the quality and reliability of their journey and undermining confidence in the system.
It is an unthinkable challenge to persuade an office worker who has missed his meeting because of strikes, a commuter forced to stand elbow to elbow every morning, or a family whose children are sick after being packed in overcrowded carriages that the UK railway is a runaway success.
The very record passenger numbers hailed by ministers and business leaders mean that the service many endure is now intolerable.
Passengers no longer trust their operator to deliver them on time and in comfort.
Paul Maynard, the Rail Minister, is all too aware of this.
Since assuming responsibility for the railways in July, Mr Maynard has made it his priority to convince train companies, regulators and officials to put passengers at the heart of everything they do.
The minister is under no illusion that the more this vision comes to pass, the more people will travel and the harder it will become for operators to preserve the trust of their passengers.
But it would be a clear sign of defeat if the Government set its sights on declining ridership in the future.
The way in which operators accommodate millions more passengers while also preserving trust in the network is one of the biggest challenges the railways face.
To make it even harder for the communications teams charged with keeping passengers, politicians, shareholders and regulators onside, the railways are at present being convulsed by strikes and the Government’s efficiency drive.
The RMT is waging an existential struggle on the Southern, Northern and Merseyrail networks.
Passengers caught in the crossfire may sympathise with drivers and guards, while also welcoming the Government’s determination to stamp out inefficiency and rising costs. But their sense of anger and frustration is palpable.
As ministers grapple with strikes in the North and South of England, their French, Dutch and German counterparts are casting an eye across the Channel.
The operators of Southern, Northern and Merseyrail are all part-owned by European governments. They are all here learning how to operate in a liberalised rail market.
Unions and their supporters in Parliament decry what they see as UK taxpayers funding dividends to state-owned entities from France, Germany and the Netherlands. They want the railways to be re-nationalised.
Even if the last Tory Chancellor in effect re-nationalised the fixed railway by putting Network Rail’s debt back on public books, this Government has no appetite for a major shake-up of operations.
Mr Maynard, his officials, the operators and their overseas shareholders are bracing for more pain.
Some may even call it success.
Philip Pank is a partner at Engage by Bell Pottinger and oversees the company’s transport portfolio. He was previously transport correspondent at The Times.