Identifying the Lead Domino

In terms of deciding the specificity of what a give habit might be, it strikes me that any goal can be broken down into smaller steps. Where do you draw the line? I just use an example. Say say, all right, i want to lose five pounds. That's my one thing. No, that's the result that you're looking for. The one thing is that if you just knock that down, everything else becomes easier or n necessary. This is what we call identifying the lead domino.