Three weeks after the spectacular jewel theft at the Louvre, the museum has been heavily criticised for neglecting security.
The Court of Auditors report, drawn up before the heist, found that for years managers had preferred to invest in new artworks and exhibitions rather than basic upkeep and protection.
Let no-one be mistaken: the theft of the crown jewels is a resounding wake-up call, said the court's president, Pierre Moscovici.
In broad daylight on Sunday 19 October, thieves broke into the Louvre's first-floor Apollo Gallery. Using an angle-grinder to open display cases, the gang made off with €88m (£78m) of jewels that once belonged to 19th-Century queens and empresses.
Basing its findings on the years 2018 to 2024, the report says the Louvre favoured operations that were visible and attractive at the expense of maintenance and renovation of technical installations, notably in the fields of safety and security.
In the period studied, it found the museum spent €105.4m on buying new artworks and €63.5m on exhibition spaces.
But at the same time it spent only €26.7m on maintenance works and €59.5m on restoration of the palace building.
The findings chime with other criticisms, such as from Culture Minister Rachida Dati who said managers had grossly underestimated the dangers of intrusion into the museum.
One of France's leading art experts, Didier Rykner, has also accused the museum of preferring to spend its abundant resources on eye-catching initiatives rather than basic protection of what it already has.
One possible casualty is the Louvre's ambitious New Renaissance project which was launched with fanfare earlier this year by President Emmanuel Macron and the museum's director, Laurence des Cars.
The plan includes a new entrance at the eastern end of the Louvre, and the excavation of new exhibition spaces including a separate gallery for the Mona Lisa.
But the Court of Auditors found that the project had been undertaken without proper studies - either of technical and architectural feasibility (or)… financial evaluations.
The projected cost had already soared to €1.15bn, it said, compared with the €700m announced in January.
In its response, the Louvre said it accepted most of the court's recommendations, but it believed the court did not fully understand all that it had done – notably in security.
When it comes to the biggest and most visited museum in the world, the only balanced judgment is one that looks at the long term, it said.
Meanwhile, it has been revealed that one of the suspected thieves, named as Abdoulaye N, 39, was for many years considered a local hero in the Aubervilliers neighbourhood of northern Paris, renowned for his often illegal feats of motorcycling.
Going by the nickname Doudou Cross Bitume, he regularly posted videos of himself performing skills on a motocross bike – such as wheelies at Paris landmarks like the Trocadero.
Abdoulaye N was previously a guard at the Center Pompidou in Paris, an arts centre containing Europe's largest museum of modern art.
He had a number of convictions for traffic and other offences, but nothing linked to organised crime.
According to French media, his profile – and that of the other main suspect Ayed G – suggests they might have been petty criminals possibly in the pay of a wealthy third party.
Two other people are in custody, including a man suspected of being an accomplice who waited with getaway motorbikes outside the Louvre, and his wife, who faces a possible charge of conspiracy.
The fourth man at the scene is still being sought – as are the jewels.
Investigators suggest Abdoulaye N and Ayed G made surprising statements during interrogations, with Abdoulaye reportedly unaware he was breaking into the Louvre while Ayed assumed it would be empty because it was a Sunday. In reality, the museum was open and filled with visitors.
