Semantics, I suppose. Capability allows the market to exist and creates potential for demand. For certain levels of actual demand and saturation, social/cultu

Semantics, I suppose. Capability allows the market to exist and creates potential for demand. For certain levels of actual demand and saturation, social/cultural normalcy and expectations might lead to "need" as you describe it. But in this case, I meant specifically that Webb, given 20 yrs of remaining fuel, won't suddenly "need" refueling if the experimental technology suddenly becomes avaliable in 19 years, as the remaining system also approaches end of life. Fuel is no longer the most likely point of failure for determining lifespan. That might have been different if Webb had to use more fuel on its trajectory burn, had only a few years of fuel, and the technology was extant/eminent and cheap. The risk-v-reward calculus would completely different, but unlikely to change at this point. If my truck throws a rod on a roadtrip in Alaska and I limp upon a gas station as my 20yo dying truck burns the last of its gasoline... I don't "need" gasoline, I need a flight home and a new truck.