For a long time, I resisted to-do lists. I wanted the flexibility. I felt that if I kept a list, it would tie me down to a particular set of tasks. Gradually, though, I came around. The busier my work life became, the more crucial it was to have some sort of running agenda on hand. Before long, I even started adding some of those items onto my weekly calendar. In other words, I’d reluctantly become a planner.

Looking back, it shouldn’t have been so difficult. In fact, there are at least three psychological benefits to the simple act of drawing up a list of top-priority tasks–whether or not you actually accomplish them.

Writing Makes Your Memory’s Job Easier

Keeping a list of tasks you need to perform is like taking notes when you’re reading a book or listening to a lecture. When you take notes, you need to filter external information, summarize it in your head, and then write it down. Many studies have shown that note taking helps us distill the information we hear and remember it better than we would if we’d just heard or read it.

Writing a to-do list is a similar mental experience. Even if you first spend some time thinking about the tasks you have to do, the act of drawing up a list and prioritizing the items on it forces you to do a little extra work.

This matters. Your brain decides which pieces of information to hang onto for later, partly as a result of how much work you do to them up front–so the more you mentally manipulate a piece of information, the better you’ll remember it. That’s why it’s sometimes surprisingly easy to remember what’s on your to-do list even when you aren’t looking at it.

Planning Turns Abstract Goals Into Concrete Work

For most people, the challenge at work isn’t keeping busy hour by hour or day to day, it’s making sure we get the big-picture projects done that make work fulfilling. These are often broad, abstract goals that you hope to achieve over a period of weeks or months. The problem, though, is that they’re hard to achieve without breaking them into a coherent set of concrete actions you can take on a daily, weekly, and monthly basis.

Suppose you’re trying to write a book. You can’t do that without taking the time to do research first, then put in the hours writing, and finally spending time editing what you’ve written. All that takes time, and keeping an agenda of all the little “sub-goals” that will take you toward the larger, more abstract one can help you actually get you to a finished manuscript you’re proud of.

As you think through these smaller tasks, other steps will often occur to you–some that you hadn’t originally envisioned needing to take when you first set your overarching goal. They weren’t obvious until you actually thought about everything it would take to reach it. So even if your agenda changes in practice as you work toward your objective, the process of thinking ahead about the steps involved can help prime you to do the work ahead.

It Helps You Clear The Weeds You Couldn’t See

To-do lists go unfinished for lots of reasons. Workplaces are distracting and full of unforeseen events. The daily flow of email and team messaging tools regularly threaten to drown out other activities–and that’s not to mention the meetings you’re constantly getting pulled into.

But once you write down the tasks you need to perform, you then have to clear space in your day to put some of those tasks onto your calendar. This calendar maintenance is itself a useful exercise for fighting the tide of interruptions you’re always facing. It pulls your brain out of a reactive mode and forces you to think about the long term. Plan your to-do activities a few weeks ahead when your calendar still has some blank spaces in it. Add in time for the tasks that are crucial for achieving those long-term goals.

You may also find you don’t have enough space in the calendar to make that happen–and that’s okay, too. When that happens, it’s a good sign that you’ve been loaded down with other, less-important jobs that are crowding out your most important work. And chances are it was difficult to see that before sitting down to manage your calendar.

If you have control over your own schedule, it may mean it’s time to reprioritize the major elements of your workday. If your schedule is driven by someone else’s requirements, then use it as Exhibit A in a meeting with your supervisor, and try and press for some changes. Lay out the key goals you want to achieve and point out how little time there is in your schedule to make those happen. Maybe you can delegate some things to free you up.

But the point here, anyway, is that you can’t do any of this without first jotting down a to-do list. So even if it isn’t that well organized and some of the items on it fall through, you’ll still have managed to step out of the normal flow of things. That way, you’ll be able to look ahead to uncover whatever might be getting in your way that you couldn’t see. And that may be more important, in the long run, than crossing an individual task off of your list in the short term.

Productivity tips from the world’s busiest people