Everyone of us lies somehow. There are a lot of reasons why people lie to each other. For instance, save relationship, have more money or feel more confident. It is a hard question because it depends on people and what they want to keep a secret.
As for me, I am always trying to tell the true and do not exaggerate reality because life is getting easier and happier. It means that I am in harmony with myself. That is why my favourite phase is “honesty is the best policy”.
Eventually, you should be honest with yourself and if you do it you will be honest with your surroundings.