Be About it

Don't make a pattern of letting people down. It is entirely within your control to do what you say you're going to do, because if you're not confident you will be able to do something you don't need to say that you will. This is true in jiu jitsu and it is true in life. If you need to tell other people so that you are accountable, then I think establishing consequences if you don't meet those goals is reasonable. Be a person of your word, it is a valuable life skill, and it establishes that you are a person who can be trusted. Don't talk about it, be about it.