In life, we complete projects. We pay off debts. We reach goals. We lose things. And, in this completion/finishing, a void is opened up. As you see something coming to an end, it is critical that you begin planning on how you will replace it. What will you do so that a pointless (or worse, negative) thing does not stand in its place. When you come to the third to last chapter of one book, begin looking for another to read. As you’ve hit the goal for one muscle group, have another target group that you would like to work on ready to go. But don’t let (too much ) time pass idly. It is the quickest way to fall into a bad habit that holds you hostage.
You have 24 hours in a day. Use them all effectively.
Make professional development a priority.