I took a statistics class in college (actually it’s statistics and probability). I realized all of it was just opinion, not fact, not science.
You take a small sample and try to extrapolate it to tens of millions of people. Example: I have no idea who was polled, but it was not the Heartland, when it came to Trump. He was given a 2% to 3% chance of winning.
I had done my own polling in my hometown, which had been Democrat since forever. All I heard was “Trump, Trump, Trump.”
My hometown was a middle-class steel mill town with the steel mill now out of business. I extrapolated that to rest of the U.S. and realized Trump was going to destroy Hillary Clinton.
I was right; that is exactly what he did. I knew it was going to happen, beyond all doubt.
The only part of the country that matters politically is the Heartland. Flyover Land. Los Angeles and New York City don’t count at all.
Perhaps the next Presidential election the pollsters will grow some brains and ask questions in Missouri or Tennessee. Because those states matter a lot more than New York or California.