Myself and those who I have studied with attribute this quip to Rudolf Dreikurs. He used it to describe people who over use the word “should.” It’s a simple word, but holds significant, and often unrecognized, meaning. It means there is something has not happened, is not happening, or will not happen that we think ought to. This is fine as so far as it’s limited to awareness. Instead, it is often accompanied by feelings of sadness associated with inferiority. You think a worthwhile and deserving person would be further or higher, and since you’re not there the only logical conclusion is that you’re not worthwhile or deserving.
Perhaps an example would help. Many of the people I see have issues with anxiety. They think or say things like “I shouldn’t get so anxious” or “I should be able to shake this” and so on. This means there is some ideal level of ability to manage anxiety or express your worries in a healthy way and you not possess that ability. If this were where the though process stopped, that would be fine. If it were only awareness of where you are and where you want to go, it would be a great step to getting there! However, if this were as far as it was being taken, you would have thought “I need to manage my anxiety better” or even “I want to be less anxious.”
Well, that’s not what you thought. You used the word “should.” So you acknowledge where you are and where you want to be, but then placed some value on your self worth based on your perceived inferior position. You are making the claim that you’re not good enough or don’t deserve to be where you would like to be. The problem is if you don't believe you deserve better, you will not be willing to get better.
So know you’re going about life acting like a person who doesn’t deserve to be happy. You hope somehow one day you’ll get up and act like someone who deserves to be happy. I’m not sure why you would happen upon this motivation or encouragement. Even if you were willing, how would you be able? Getting down on yourself for not being where you would like and beating yourself up about the growth you want to make doesn’t give you even a hint of an idea about how to get there. In fact, it occupies your time worrying about not being there rather than making a plan.