My beach read in Mallorca in May was not some plot-driven thriller, or high-octane, high-stakes love story with an embossed cover picked up from an airport display. It was William Gaddis's 900-page, multi-layered and sometimes dashed-confusing behemoth The Recognitions. I'm not trying to boast (my bookshelves hold as many guilty pleasures as anyone else's) but to make the point that I, as an average reader, along with many others, am sometimes drawn to complexity and experimentation over plot. But would The Recognitions get published were it submitted by some eager unknown today (as Gaddis was in 1955)? I hope it would: the story of an art forger, a metaphor for the lack of authenticity in all aspects of life, it rips along wonderfully in places. But I rather suspect it wouldn't get a look in. The opening is slow and focuses on the protagonist's father. Where is the main character's dilemma? Where is the inciting incident? Where's the story?

"Films won and books lost. That's the story of the 20th century – the story of where the stories went," Toby Litt observes. An emphasis on strong plot and the rejection of fiction's digressive powers seems to be the order of the day. We just don't do longueurs anymore. The Richard and Judy culture of book clubs, while laudable in itself, demands strongly-plotted novels with likeable characters as fodder.

An example: Gary Shteyngart's 2010 novel Super Sad Love Story is full of the kind of nimble prose Nabokov would be proud of. Shteyngart is serious about fiction, frequently referencing Tolstoy and Dostoevsky and skitting on the death of the book. But there is something somehow efficient about his plotting, which charts the romance between amiable loser Lenny Abramov and Korean-American Eunice Park, as the US finds itself on the brink of economic and social collapse. Every scene advances the action: there is little room for reflection: one wonders about the degree of "tightening up" the book underwent during the editorial process and how it might have read had it been allowed to breathe a little more.

I often wonder if relentless focus on plot is edging something of value out of our literary culture. Creative writing students are frequently told to "show not tell", to "get into the scene early", and make sure their characters are never without motivation. All great advice, except it doesn't really reflect the way life is. Would-be novelists must submit three chapters and a synopsis of their manuscripts to the literary agents or publishers they approach: if these fail to "hook" early on they will almost certainly be rejected. So what would happen to Nausea, The Unnamable, In Search of Lost Time, or, God forbid, Finnegans Wake? I recently attended a talk where a leading London literary agent stated that, in his opinion, it is highly unlikely that Kafka would get published as a first-time writer today. Of course there's no way this can be verified, but if true it's a pretty sorry state of affairs.

There are always exceptions to the rule, and the popularity of David Mitchell and Roberto Bolano is encouraging, as was the excitement around the publication of David Foster Wallace's The Pale King earlier this year and Tom McCarthy's shortlisting for the 2010 Booker prize for C. McCarthy has said that "it seems to me that a lot of contemporary writers are shirking their duty to deal with the legacy of modernism and that many of them don´t care". Art has occupied the experimental space that literature did in the 1920s, "maybe because writing is too commercial". In order to be read widely, writers must go through the major publishers who are beholden to their shareholders, and therefore to market forces. What gets published, in other words, must please as broad a swathe of the market as possible.

Plot, as one of many literary strategies, is fantastic: employed carefully it can lend extraordinary emotional resonance to a text. But we shouldn't lose sight of the fact that it is not the only pleasure to be derived from great literature. Toby Litt on films again: "In the end, books are better than films at putting you inside someone else's head." Film focuses on plot: on external action. The novel can do something different: it can show us how we think. A loosely-plotted book like Nausea can tell us more about the being alive than a tightly-plotted thriller and it will probably be more truthful. A commercially-driven literary culture too prescriptive in its demands on fledgling writers means we are in danger of missing out on the new Gaddises, Becketts and Joyces who could enrich our culture and our understanding of ourselves.