The reality is that the trust battery is a summary of all interactions to date. If you want to recharge the battery, you have to do different things in the future. Only new actions and new attitudes count.
— It Doesn't Have to Be Crazy at Work
You can't expect people to trust you right off the bat and you can't expect them to trust you after you've abused it in the past. This goes in both directions—from above and from below. If your boss takes advantage of you, you won't want to help them out and if you do the same to them, they won't be so keen on giving you any slack.
So be good to each other, keep your promises, and make sure the battery stays topped up.