Got downvoted twice already!

  Got downvoted twice already but I don't know why! Yes I uploaded content that wasn’t mine but I label it properly. I own an image collection since 1993 (when I got my first pc, 1994 my 1st internet connection) I can’t know the source of every single image I upload. On the other hand a youtube video I uploaded so I can comment on it got donwvoted too, do I have to post +300 words posts every time or why do I get downvoted by this “cleaning” accounts  

Anybody dealing with the same?

source: https://pixabay.com/es/idk-no-lo-s%C3%A9-mensajes-de-texto-1934218/