Friday was "a horrible day" for investors in Duolingo, reports Fast Company. But Friday's one-day 14% drop is just part of a longer story. Since last May, Duolingo's stock has dropped 81%. Yes, the company faced a social media backlash that month after its CEO promised they'd become an "AI-first" company (favoring AI over human contractors). And yes, Duolingo did double its language offerings using generative AI. But more importantly, that summer OpenAI showed how easy it was to just roll your own language-learning tool from a short prompt in a GPT-5 demo, while Google built an AI-powered language-learning tool into its Translate app. And yet, Friday Duolingo's shares dropped another 14%, after announcing good fourth quarter results but an unpopular direction for its future. Fast Company reports:On the surface, many of the company's most critical metrics saw decent gains for the quarter, including: — Daily Active Users: 52.7 million (up 30% year-over-year) — Paid Subscribers: 12.2 million (up 28% year-over-year) — Revenue: $282.9 million (up 35% year-over-year) — Total bookings: $336.8 million (up 24% year-over-year) The company also reported its full-year 2025 financials, revealing that for the first time in its history, it crossed the $1 billion revenue mark for a fiscal year. But the Motley Fool explains that Duolingo's higher ad loads and repeated pushes for subscription plans "generated revenues in the short term, but made the Duolingo platform less engaging. Ergo, user growth decelerated while revenues rose." Thursday Duolingo announced a big change to address that, including moving more features into lower-priced tiers. Barron's reports:D.A. Davidson analyst Wyatt Swanson, who rates Duolingo stock at Neutral, posited that the push to monetize "led to disgruntled users and a meaningful negative impact to 'word-of-mouth' marketing." Duolingo has guided for bookings growth between 10% and 12% in 2026, compared with the 20% rate the company would have expected to see "if we operated like we have in past years...."If stock reaction is any indication, investors are concerned about Duolingo's new focus.Read more of this story at Slashdot.