IMO the polls didn't take into account one thing.
That the perception of Hillary being low energy and not doing enough campaign events was also the reality. The campaign never went to Wisconsin or into rural areas to hold rallies, but I lost track of how many fundraisers they had. It just fed into the perception that she didn't care about regular people. Not having events in these places led potential Hillary voters to become extremely demotivated or go and change their mind.
That the perception of Hillary being low energy and not doing enough campaign events was also the reality. The campaign never went to Wisconsin or into rural areas to hold rallies, but I lost track of how many fundraisers they had. It just fed into the perception that she didn't care about regular people. Not having events in these places led potential Hillary voters to become extremely demotivated or go and change their mind.