How do you explain the Mandela effect?

How do you explain the Mandela effect?

I distinctly remember Pikachu having a black tail like the one in the picture. But if you go and google Pikachu you will see his tail is all yellow.

fabricated memories
the first time you read somewhere "hey didn't pikachu have a black tail?" you imagined pikachu with a black tail and now you falsely remember it like that

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Human memory is horrifyingly inaccurate.

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You are stupid

This really makes me wonder how many of my memories are totally inaccurate. Spooky.