Is there a psychological word or diagnosis for people that can t stick to or maintain changes or habits etc?

This is not necessarily a particular disorder. It could be more like a personal weakness, a trait of character or temperament, or behavior that was learned from parents. Some people are more driven or motivated to do self-improvement, for various reasons. Others may not have the confidence that they can improve--unconsciously they may fear failure, so they don't try, and this fear could have been instilled by their upbringing (being belittled by adults). Often people who are called "lazy" are really just lacking in self-worth; it's easier not to try and to just live in the imagination of what could be instead of forming goals and trying to fulfill them. However, there are people with attention deficit problems who cannot concentrate on a task or keep up their efforts. Sometimes a person just has a mind that is constantly moving. He will get into a habit for a while, but then his mind will get distracted by something else and he will forget all about his previous determination to cultivate a certain behavior or practice something regularly. If he recognizes this trait in himself and really wants to overcome it, then he will have to look for self-help and work hard to change.

Not everyone can be a genius and not everyone will be a star. Sometimes self-acceptance is the most important thing to cultivate. If you can accept yourself as you are, and feel that you are a valuable person even with your faults, then from there you will value yourself enough to believe that you can do more with your life. We all have more potential than we realize.

NOBODY is "inspired" and "motivated" to clean the house. You have a false belief about why people do things. This isn't a psychological issue, you're just lazy. I don't like cleaning the house either, but I make myself do it so it's not a festering pigsty.