Can someone explain why supports blame their adcs because of steryotypes

I just got out of a game where my support was verbally attacking him for being a “useless add” because vayne needed to farm a little and not go in when the soraka was building full tank. Why do the adcs get the stereotype for whining when the supports mess up as much as them Also I’m talking about the ateryotpe where adcs are considered crybaby’s
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