Why does the context menu say "Translate Selection to Dutch" unless selection is long enough?

If I select (highlight) one word, or a small number (~3) and right-click, the context menu will always display "Translate Selection to Dutch" as one of the options. If I select a few more, it will switch to "Translate Selection to English" (assuming that what has been selected is not English). Example: "rouvre la porte" vs "rouvre la porte au nucléaire" I have English (United States) [en-us] and English [en] in Settings as my "Website language". Possibly related: full page translation always defaults to English, too. Thanks in advance.