Can't say for sure, but Neeva I don't think failed because they couldn't keep the business going. It was always a game of perseverance going up against Google Search that not only is free but has tremendous distribution advantages (through Android and Chrome).

DuckDuckGo is at it after all these years, building it brick by brick, if you will. Neeva's problem might have been the opportunity cost to their engineering and executive orgs in pursuing such a drawn out build. They'd rather latch onto something that could grow much faster, and frankly, Enterpise + LLMs is right in their alley. It is a nice pivot and not representative of much else (don't mean to discount that consumer products are hard, especially when the competition is BigTech themselves).