I think her campaign was assured that this time around there would only be token opposition to her candidacy. Having to actually respond to the presence of Bernie Sanders on the ticket is something she did not expect. Having to earn the votes of the left and progressives is something she was not happy having to do.
Fear of the republicans was supposed to be enough to get her the nomination but it is possible that her campaign never quite figured out how angry and oppositional to conservative-wallstreet we progressives have become. Many of us were never entirely satisfied with the idea of Hillary Clinton last time around and thought she was a bit too friendly with business. In a period after a financial collapse, and citizens united, and trade deals, we have begun to see a spiralling away from the interests of workers and average citizens and a movement towards increased corporatization.
Secretary Clinton has been running for the presidency for nearly a decade now and her campaign has been effective at attempting to access the mood of the democratic party without getting to the specifics in terms of policy. She gives us a lot of platitudes but has been shy on specifics (until very recently) of policy.
Even her policies aren't really that aggressive in terms of change and seem more directed at giving a thousand dollars or so for each employee that a business trains. The problem with this is that it only encourages businesses already providing training to apply for that money for existing programs in place. It really doesn't solve the problem and tax credits to businesses are among the worst ways to stimulate economic growth. In this way, her economic solutions actually are more regressive and less ambitious than President Clinton's were in the 90's.
The difficulty I have is that all the people calling on me to be pragmatic in supporting her either don't seem to pay attention to the contrasts in policy between Clinton and her chief rival or they don't mean for me to pragmatically vote in my own interest.