A union is a new concept for most marginal workers. This means that for them to make the leap, they've got to overcome their uncertainty. If a company can cast even a little doubt, it can be tremendously effective.

The traditional way to overcome this is to have coworkers be the ones advocating for a union, not staff. This is really hard at Amazon because of the high turnover. If you look at JFK8, Smalls was a manager, i.e., one of the only people not turning over every 3 months.