It’s remarkable how many “unfilmable” books have been, well, filmed. With this week’s news that Neil Gaiman’s sprawling comic-book series The Sandman has been acquired by Netflix, fans have been excited, if tentative, no doubt remembering the long history of attempts to adapt the 75-issue story that was often dismissed as too difficult to get on screen.

As Gaiman once said: “I’d rather see no Sandman movie made than a bad Sandman movie.” Multiple scripts were written throughout the 1990s, there was a TV show in 2010, a film in 2013, an attempted rewrite of that film in 2016 – but none of this means that Netflix’s latest literary project is doomed to fail.

For “unfilmable” is often just code for “we tried and it didn’t happen”, an excuse for all the films trapped in development hell, such as John Milton’s Paradise Lost (Bradley Cooper was once lined up to play a hunky Lucifer), and the long-awaited adaptation of Cormac McCarthy’s Blood Meridian. “Unfilmable” can also mean “we tried and did a terrible job”. Stephen King’s Dark Tower series is not unfilmable, but the 2017 take starring Idris Elba and Matthew McConaughey might make you wish it was. Or the maddening works of William Faulkner, most recently put on screen by actor James Franco, who took time off from insisting he can write novels to ruin someone else’s by directing, adapting and starring in As I Lay Dying in 2013 and The Sound and the Fury in 2015. Or Ayn Rand’s Atlas Shrugged: three films and three terrible decisions came in 2016 when reviews for part one (“sits there flapping on screen like a bludgeoned seal” declared Rolling Stone) did nothing to dissuade the great minds behind it, who turned their backs on the free-market to supply two sequels in the face of no demand. (Part two: “The film’s excruciating unwatchability transcends politics”; part three: “Cut-rate to the point of incoherence.”) And unfilmable can even apply to books that prove to be brilliant on camera: the new TV show of Joseph Heller’s Catch-22, the Wachowski sisters’ take on David Mitchell’s Cloud Atlas, Paul Thomas Anderson’s 2015 film of Thomas Pynchon’s Inherent Vice.

Tom Hanks and Halle Berry in Cloud Atlas. Photograph: Allstar/Warner Bros. Pictures

For many of the books that Hollywood once clinked together its last coppers over, Netflix is barrelling in with a cash cannon and letting it rain. Because unfilmable also means “unaffordable”. Aside from The Sandman (which is being billed as the most expensive TV show DC Comics has been involved in), Netflix has scooped up books that promise to be CGI-heavy (The Witcher, out later this year; a Roald Dahl animated series).

Henry Cavill in Netflix’s upcoming fantasy series The Witcher, adapted from the books by Andrzej Sapkowski. Photograph: Netflix

Unfilmable also works as a stand-in for another euphemistic label: “uncommercial”, which often just means “with subtitles”. This once got in the way of books such as Gabriel García Márquez’s One Hundred Years of Solitude, which the author insisted for years must be told in Spanish and would not work as one feature film. As one of his sons said earlier this year, when announcing Netflix was making a Spanish-language serial: “In the current golden age of series, with the level of talented writing and directing, the cinematic quality of content, and the acceptance by worldwide audiences of programmes in foreign languages, the time could not be better.”

So has TV ended the age of the unfilmable book? Is any book truly limited to the page? Perhaps unfilmable now simply means books often declared “unreadable” – so a lot of modernist novels that are heavy with lyricism, ambience or internal dialogue: James Joyce, Virginia Woolf, Djuna Barnes. Or the obvious, impenetrable contenders with Matryoshka doll plots: Infinite Jest by David Foster Wallace, Gravity’s Rainbow – Pynchon again – and Dhalgren by Samuel Delany. Or books with footnotes: House of Leaves by Mark Z Danielewski, Pale Fire by Vladimir Nabokov. (Though the recent Amazon/BBC production of Good Omens, another Gaiman vehicle, proves it is possible to translate narrative meanderings on screen.) We’ll have to wait and watch.