Because there are many factors which go in to decisions and a particular negative feature might be outweighed by other concerns? Also, pedantic point, I think

Because there are many factors which go in to decisions and a particular negative feature might be outweighed by other concerns? Also, pedantic point, I think you were looking for the phrase en masse, of french origin. See https://en.wiktionary.org/wiki/en_masse https://en.wiktionary.org/wiki/en_masse