#1) They were cool
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Leaving aside all the other reasons on this list, though, this one is the most important when it comes to getting over with casual professional wrestling fans: you need to be cool. And, that's exactly what The Shield were with their vests, entrances through the crowd, and no-nonsense attitude.
Everything about them just screamed "cool", and that did wonders for their image in front of the WWE Universe.
Edited by Shruti Sadbhav