Earlier quoted context omitted.
The text in question: > Highlighting or tapping any word will send the requests with the text to Bing Translate and Wikipedia, as well as back to Amazon. Is there a reason why that text needs to be sent before the user clicks the "translate" button? Is there a reason why it needs to be sent to Amazon?
> Is there a reason why that text needs to be sent before the user clicks the "translate" button? Yes - UX latency. I would expect this kind of thing to take a few thousand milliseconds, and shaving off a few hundred milliseconds from between when the user highlights text and when they select "translate" is significant. The fact that this data is being sent to Wikipedia of all places further signals that the usage is…
I was wracking my brain on this, and all I could come up with was "to independently verify the invoicing for Bing translations" and "how many times are people accessing the definition/translation and not highlighting". So, analytics, not something that explicitly benefits the user.