If you are unreliable it doesn't matter what your other virtues are, you will fail. Doing what you say is key to being a great founder. If you learn this skill you will learn to trust yourself and your confidence will grow. People will trust and respect you and you will get more done.
When someone says they are going to do something and then does it, again and again, everyone learns that they get things done. People start treating them, and their goals, with respect.
Poor founders are sloppy in their words. They don’t do what they say and they don’t follow up. They don’t write down and define things they agree to and as a result people don’t trust or respect them, and they don’t trust themselves.
The solution to this is impeccable agreements. That is whenever you agree to something you (a) precisely define it and (b) write it down. A precisely defined agreement is one in which you know who will do what by when and a third party can objectively judge if the agreement was fulfilled or not.
For example:
To become the type of person that always does what they say they will review these tiny habits until they become second nature. If you are managing a team, have all your team members make these three habits second nature.