During testing, the device came out less trained than Siri and Apple's Google Assistant. Alexa has also been accused of extracting conspiracy theories and "cacking" inappropriately.
Loup Ventures researchers asked the three robots 800 questions, divided into five categories, to assess their ability. They looked at knowledge, such as "Where is the nearest coffee shop?" And "Can you ask me for more paper towels?"
Other categories included giving directions, providing information about a sports accessory and asking for a reminder to call a friend later that day. The Google Assistant understood all the questions and answered 86% correctly.
Siri came in second after obtaining 79% of the reason. But Alexa only correctly answered 61% of the questions and misunderstood. 13. Microsoft's Cortana, which has a smaller market share, made it even worse, answering only 52% and misunderstanding 19.
In their report, analysts said: "We found that Siri is a bit more useful and versatile (responding to a more flexible language) by controlling her phone, her smart home and her music.
"Apple, true to its roots, has ensured that Siri is able to listen to music on both mobile devices and smart speakers." The report said that all devices continued to improve.
They said: "Both the voice recognition and the natural language processing of digital assistants in general have improved to the point that, within reason, they will understand everything you tell them."
Siri, the oldest of the products, is more closely associated with the iPhone. Amazon's Alexa can also be used on phones but is associated with the company's Echo smart speaker, on the left.
The Google Assistant is used both in the Google Home speakers and in the firm's Android phones. The famous chef Gordon Ramsay has achieved his own "skill" Alexa.
The downloadable plugin works when you say: "Alexa, enable Gordon Ramsay." Once lit, it will give you Gordon's angry advice about whatever kitchen you've been doing.