04/02/2014 03:39 pm ET Updated Jun 02, 2014

6 Reasons Why Time Management Is Hard

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There's never enough time. This is not a new insight, but the pace of life and the demands on our time have gotten worse. Time is a scarcer resource than money. Yet, even as money management products proliferate, the tools we have to manage our time -- such as the calendar and the to-do list -- have not changed much in the past century. One reason is time is harder to manage than money. For one thing, it is a perishable resource (there's no bank for time). But the challenges run much deeper. If we want to understand what tools are needed in the hectic 21st century, we need to understand these challenges. Here are six.

1. It's not obvious what's important. Your preferences aren't obvious to you. How do you trade off finishing that report with going to Johnny's soccer practice? In the language of decision theory, you don't know your utility function, or rather, the mathematical value of every action you might take. Said more simply, you often don't know what you really want. How can you optimize decision making if it's not clear what you're optimizing for?

2. Too many things to consider. Even if you did know your utility function, there's just too much going on. Think of all the things vying for your time -- work meetings, social engagements, family, errands, hobbies, health maintenance. First, it's hard to remember them all, along with the various constraints and preferences you have. But suppose that all these were all laid out clearly in front of you, nothing escaping your attention. You'd have what computer scientists call an intractable computational problem, meaning that there is simply no algorithm that can quickly determine how best to allocate your time. And what's hard for computers is impossible for people.

3. Stuff happens. Life isn't static; your co-worker calls you into a meeting, your kid got sick and must be picked up from school, you received a call from the Nobel Prize committee (two of these three things happened to me). You need to constantly re-adjust your plans. This turns a hard static optimization problem into a much harder dynamic one.

4. Other people want your time. You're not the only one who wants to spend this currency called "your time." Others want to spend it for you. Just look at your calendar and see how much of it is taken up by meetings initiated by others. The problem is that our psychology and our social norms make it hard to say no.

5. We're human. We constantly mismanage our time. We procrastinate; we go for the fleeting immediate gratification of checking off a bunch of easy tasks and let the critical hard tasks languish; we spend valuable high-productivity periods on mindless email triage. We make mistakes.

6. Technology has made things worse. Ironically, technology has exacerbated several of the problems. Laptops and cell phones allow us to do things at more times and places than ever before, meaning there are even more possible activities to consider when deciding how to spend our time. Perhaps more acutely, technology increases the social pressure on our time, since other people can reach us at almost any time or place.

So, what can be done about these challenges, and what does this tell us about time-management tools in the 21st century? There is no silver bullet, since the underlying cause will not disappear -- the pressure on our time will likely not abate soon. But here are a few takeaways on how tools can help. First, the traditional calendar isn't the solution; it is fundamentally a record of the time-currency we have already spent, but it doesn't tell us how to spend what's left. This is not to say that the traditional calendar is not useful; it is a great device to coordinate among people, and is a good reminder of what we did or intend to do. But we need much more.

We need tools that present to us in one place the various things that vie for our time, and help us perform the optimization among them that is so hard. Tools should help us realize our own preferences about how to spend our time, if only by encouraging us to pay attention. They should be flexible enough to accommodate the dynamics of life. Tools should allow us to be "responsibly social" and encourage us to provide our time with the protection it requires. Tools should nudge us to do the right thing, mitigating our sometimes counter-productive tendencies. If they do all this, technology will once again be our ally in our most important quest in life -- spending time on what really matters to us.