Do I really need a variable-temperature kettle?

If you drink green, white, or oolong tea, or you brew pour-over coffee, yes — those styles want water below a full boil (typically 160–205°F), and reviewers consistently report better flavor with precise temperature control. If you only make black tea, French press coffee, instant noodles, or hot cocoa, a straight 'boil only' kettle is faster, cheaper, and one less thing to break.