See the part of the sentence that said "They didn't do much." Anyone can write the same song a thousand times. On the other hand, The Beatles (arguably) invented -- and innovated. And they did it well. And they took risks doing it. They wrote similiar or same-sounding songs for an album or two and then just went right into experimenting, right into making complex masterpieces (and, again, I'm not even a big fan of their work -- but I definitely think they're extremely important). That's inspiring and influential and yada yada.
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