Change can often be a challenge, and this is especially true when the need for change is coming from the outside. Someone thinks we need to change, or someone else wants us to change. It doesn't matter if it is as simple as how we do things, how we talk, and such, or as complicated as changing our complete lifestyle. We've got all these beliefs and habits mixed all around in there, and all of that creates reluctance, which is another r-word for resistance. Some of that might even create a rebellion, which is resistance on a more massive scale.
When change is desired from within, resistance is less if not completely missing, and can be replaced with eagerness.
Just because we are saying to ourselves, “I should change, I need to change, I ought to change this, this is not coming from within. It is coming from without. When it comes from within, it comes with desire, eagerness, fun, delight.