Getting people out to vote against someone is hard, as many Republican candidates from the primaries can attest in their battle to defeat Trump.
Add in the echo chambers that supporters created for themselves they created the self delusion that they were far more numerous than required to defeat Trump. Reinforcing that were numerous polls saying that Hillary was ahead.
I think the ads played minimal impact other than showing colors and telling motivated voters that they weren't alone.
Hillary never gave anyone a reason to vote FOR her.
Pretty simple.
Based on your comment, you might appreciate this from https://t.co/oeab8Ge9fF:
Dan Hopkins 11:24 PM
Is It Turnout Or Persuasion?
“As we grapple with Trumps unexpected strength in key swing states, we face a key question: Are changes in turnout or persuasion at work? Is it more about who turned out or stayed home or who changed votes from 2012 to today? And while both factors are likely at work, theres a basic piece of math that makes persuasion more likely to be the underlying driver: When turnout changes, a single vote goes into or out of a candidates column. But when a voter is persuaded to switch sides, a vote drops from one tally and joins another, in effect doubling its impact. There will be plenty of time to look at the data, but persuasion has an advantage out of the gate.”