It might be interesting to do a statistical examination of to-do lists, specifically of the length of time for which items remain on them. It might seem logical that the longer something has been on a to-do list, the sooner it is likely to get done. I doubt this is usually the case, however. Easy items tend to get added and removed quickly. “Buy soy milk” is an instruction that is likely to be followed in a matter of hours or days. Other items are likely to sit on to-do lists for months or years: “Research doctoral programs”, for instance, or “Photo project with L-series macro lens”.
One natural response to all of this is to have lists that are tailored to different timescales. Few people will retain their grocery lists for longer than it takes to acquire the desired items. By contrast, keeping a list of major long-term projects is probably a good idea, from a life planning perspective. It can be a way to check whether one’s time is primarily being occupied by personal priorities, or whether distractions are consuming most of it.
I have heard that it is a good idea to write “eat a chocolate” on your daily to do list – this way assuring that you will accomplish something that day.
I have a particular preference for striking items off my to do list – which does lead to the easier items to be struck off that can be done quickly leaving the longer items. Perhaps one way to approach the longer or more time-consuming items is to break those into smaller components.