If it isn’t scheduled in, it isn’t getting done. To-do lists are essential in that they clarify what needs doing (see tip #7), but they can make us feel like we’re doing something useful when it’s really little more than procrastination disguised as productivity. Worse, when we inevitably fail to cross off all the items on our list, they can leave us feeling discouraged and incompetent. Instead, timetable tasks that need doing, which will force you to get realistic about how long each item will take, and give you a structure in which to complete them.
Source: learn.filtered.com