When we have the to do list as a catch-all list we dilute its importance and effectiveness. It becomes just another list and the tasks remain collecting dust.
Treating the list with reverent has its benefits, giving a bias towards action. Add a task to the list (only) If it is important enough for you to do it. And if the task was important enough to be on the list then make sure you do it. Don’t have second thoughts about it. You can add a note to the task to remind yourself why you wanted to do this task, its nature, importance and the benefits of doing it.
Things do change over time. So when a task that made to the list is no longer important, take it off the list immediately. Don’t let it linger around. If you want to hang on that for keep sake, then create a (hidden) “someday/whatever” list if you want and move the task to that list. But take it out of the main to do list. Keep the list pristine and clean.
Having such a focused list keeps you motivated to get this done. A simple to do list now becomes a powerful action list.