One of the time management concepts I think is key to success is that there is an optimal time for each type of work. Of course, it is not necessarily the same time each day or each week, and there are many factors, some of them unpredictable, that dictate what piece of work would be most efficiently and effectively done at any given moment.
For example, your energy level, physical location, what you ate for lunch, how your morning meeting went, what song you heard on the radio on the drive in, are all factors in determining what work you would be best to do right now. Ultimately, these factors dictate your mental state, including level of motivation, clarity of thought and other unconscious variables that affect how well you work.
Over-planning your time to ensure that you are always working on the “best” item is not necessary, and can actually waste more time than it saves. As long as you are aware of these factors, and as long as you have a good system for managing your work, it is easy enough to make a quick decision to do one thing rather than another. Once you start making decisions this way, it will become obvious whether you are working on the item that best fits your current state.
Of course, sometimes your well-organised time management system tells you that you absolutely must knock off a specific piece of work, right now, and that work is the last thing you are interested in working on. A combination of will power and extra-strength black coffee is in order here. If this happens often, it is a signal that you need to tweak your system, since you are not seeing this work early or often enough to get it done at a more optimal time.
This concept is also a good reminder of why it is never a good idea to have your email inbox as your primary view. If you spend most of your time doing email, so many opportunities for slotting the right work into the right time will pass you by. Keep that task list front and centre, and most of the rest will take care of itself.
