Social media algorithms carefully designed to reward reckless youthful behaviour

On August 16th, a BMW carrying five teenagers drove the wrong way down the M9 near Moone, Co Kildare, and hit an oncoming vehicle head-on. All five of them died. Four people in the other car, including a seven-year-old boy, were seriously injured.Six days later, on the A66 near Middlesbrough, a car travelling against traffic struck a Cleveland Police armed response vehicle. All seven people in the two cars died.While these were separate incidents, the connection between them is difficult to ignore. Several of the A66 dead had previously posted TikTok videos of reckless driving; those videos remained on the platform after the crash. Irish media linked some of the M9 teenagers to a subculture of car theft, joyriding, and online performance for engagement. Autoplay removes the need for a decision to continue scrolling, infinite scroll eliminates the structural cue that tells a user to stopWrong-way driving incidents aren’t unknown on our motorways (one in June 2024 caused me to spend several hours gridlocked overnight near Castlebellingham) but they are becoming more frequent. Transport Infrastructure Ireland recorded 62 of them on Irish motorways by August 2026, a 32 per cent increase on the same period the year before.READ MOREThe cyberpsychologist Mary Aiken has described the behaviour as “clout chasing”, with participants engaging in hybrid behaviours such as driving while simultaneously producing content for posting or livestreaming. What makes this particularly dangerous is that the algorithm that distributes the content rewards escalation. A video of someone driving at the speed limit collects no engagement, but a video of someone at 190km/h on the wrong side of a motorway in the early hours of the morning will.'TikTok, Instagram and YouTube do not broadcast so much as they respond. Attention is measured second by second, and what they serve is adjusted to extend it.' Photograph: Anna Barclay/Getty The fear of media influencing children is hardly new. When television arrived in western households in the 1950s, it attracted criticisms that now sound familiar. Newton Minow, chairman of the US Federal Communications Commission, called American television “a vast wasteland” in 1961. The set became the idiot box, the electronic babysitter. Although some of these criticisms were true in a limited way, much of it was class anxiety about popular culture dressed up as concern for cognition. Similarly, the early-’90s criticisms of The Simpsons as a harbinger of civilisational collapse seem absurd now, not least because those early series had an almost quaint faith in the power of the nuclear family.What has changed is the feedback loop. TikTok, Instagram and YouTube do not broadcast so much as they respond. Attention is measured second by second, and what they serve is adjusted to extend it. Autoplay removes the need for a decision to continue, infinite scroll eliminates the structural cue that tells a user to stop, while an algorithmic feed matches content to preference, although whether those of the viewer or curator is not always obvious.These carefully engineered design features are currently the subject of litigation. Last month, 29 US state attorneys general went to trial against Meta in Oakland, arguing that Instagram’s infinite scroll, autoplay, and recommendation algorithms were designed to addict children. In July, the European Commission issued preliminary findings that the same features violated the Digital Services Act.Meta chief executive Mark Zuckerberg (centre) departs after testifying in a technology addiction trial at California Superior Court, Los Angeles County, in Los Angeles, in February 2026. Photograph: Mark Abramson/The New York Times The pattern extends beyond social media feeds. EA Sports generated $1.6 billion in a single fiscal year from its Ultimate Team modes, a substantial portion from the FC game (formerly Fifa). Players buy packs containing randomised digital athletes, hoping for a high-value card, without knowing the odds. The Norwegian Consumer Council documented the manipulative design in a 2022 report; Fairplay and the Centre for Digital Democracy filed an a Federal Trade Commision complaint in the US the same year, and the European Parliament called in November 2025 for social media “loot boxes” to be outlawed when they provoke gambling-like behaviour in children.Douyin, the Chinese version of TikTok, places any authenticated user under 14 into youth mode by default. Their daily limit is 40 minutes, enforced by a hard stopThese mechanisms share a design logic: they exploit the gap between decision and action. A child opening a pack does not experience it as placing a bet. A teenager scrolling TikTok does not experience it as a decision to keep scrolling, because the design has eliminated the point at which that decision would occur. The Massachusetts attorney general’s complaint against Meta argues that features like infinite scrolling are “intentionally designed to addict children”.Douyin, the Chinese version of TikTok, places any authenticated user under 14 into youth mode by default. Their daily limit is 40 minutes, enforced by a hard stop. The app is inaccessible between 10pm and 6am. The algorithm in youth mode serves science experiments, museum exhibitions, and historical material. French president Emmanuel Macron summarised the disparity in November 2025: China exports what dulls young minds while keeping what sharpens them for its own population. ByteDance builds two versions of the same product: one with structural safeguards for Chinese children, one without for everyone else.An algorithmically optimised feed can identify which content keeps a specific 14-year-old watching at 3am, and serve more of it. However, when the content it serves is a video of someone driving into oncoming traffic, and the reward structure incentivises producing more of it, the word “feature” starts to feel most inadequate.