Source: Some image uploader.
Mismatches between text and avaiable buttons can be very confusing. A common example is having “OK” and “Cancel” as options when the question asked requires an answer of “Yes” or “No”. Although that’s perhaps grammatically annoying rather than highly confusing.
This little example, however, is a gem. Selecting “Cancel” doesn’t cancel the upload, but selecting “Yes” does. I think.