How Executive Assistants Can Overcome Decision Fatigue in The Workplace

How Executive Assistants Can Beat Decision Fatigue Before It Costs Them

By 3 p.m., you’ve triaged forty emails, rebuilt your executive’s calendar twice, picked a restaurant for a client dinner, decided which of three “urgent” requests is actually urgent, and signed off on a slide deck you didn’t have time to really read. None of those decisions was hard on its own. All of them together are why your judgment at the end of the day feels nothing like your judgment at 9 a.m.

That drop-off has a name: decision fatigue. It isn’t a personality flaw or a sign you need to toughen up. It’s a well-documented cognitive pattern, and executive assistants sit closer to its edge than almost anyone else in an organization, because the job runs on a steady stream of decisions most people never see you make. This post covers what decision fatigue actually is, what the research says about how it bends your judgment, the specific decision types that drain assistants fastest, and six ways to protect your decision-making capacity without adding one more thing to your plate.

What Decision Fatigue Actually Is

Decision fatigue is the decline in decision quality that follows a long stretch of decision-making, not physical effort. Social psychologist Roy Baumeister was one of the first researchers to study this closely. His work described self-control and decision-making as functioning like a muscle: the more you use it early in the day, the less strength it has left for the choices that come later. Researchers call this ego depletion, and it shows up less as obvious exhaustion and more as a quiet shift in how you decide.

Two patterns tend to show up first. You start defaulting to whatever choice takes the least mental effort, even when it isn’t the best one. Or you avoid the decision altogether and put it off, which just moves the mental cost to later, when you’ll have even less capacity to handle it. Neither pattern feels like fatigue from the inside. It feels like you’re being decisive. You’re just making faster, shallower calls instead of the considered ones you made that morning. This is closely related to workplace energy management, since a depleted mind and a depleted body draw from overlapping reserves.

For executive assistants, this matters more than it does in most roles, because the job rarely lets you batch decisions the way other functions can. A finance analyst might spend a whole morning on one modeling decision. An assistant might make thirty decisions before 10 a.m.: which email gets forwarded, which meeting gets moved, which of two conflicting instructions from two executives takes priority, how to phrase a message that needs to sound like your executive wrote it. Each one is small. None of them are free.

What the Research Shows

Research on decision fatigue goes well beyond intuition, and it spans judges, doctors, and knowledge workers with a pattern that holds up.

One of the most cited studies on the subject followed Israeli parole judges over ten months. Researchers Shai Danziger, Jonathan Levav, and Liora Avnaim-Pesso tracked more than 1,100 parole rulings and found that the odds of a favorable ruling started around 65 percent right after a food break, then fell steadily to nearly zero by the end of a session, before jumping back to 65 percent the moment the judges returned from their next break. The cases weren’t getting weaker as the day went on. The judges’ capacity to make the harder, more generous call was.

“None of those decisions was hard on its own. All of them together are why your judgment at the end of the day feels nothing like your judgment at 9 a.m.”

That finding has been debated since, and it’s worth naming directly rather than treating it as settled science. A later reanalysis argued the pattern could partly reflect case scheduling rather than fatigue alone. But the underlying idea, that decision quality is not constant across a workday, holds up across dozens of other studies. A systematic review of healthcare professionals found that roughly 45 percent of the cases researchers quantitatively assessed showed evidence of real decision fatigue effects across diagnosis, prescribing, and treatment decisions. Nurses and physicians in fields far removed from parole boards show the same tendency toward more conservative, lower-effort choices as a shift wears on.

The volume side of this has changed too. A 2023 Oracle study of workers across 14 countries found that 74 percent had seen the number of decisions they make in a day grow roughly tenfold over the previous three years, and 86 percent said the sheer volume of data now involved was making those decisions harder to trust. Assistants have lived this directly. The instant-message pings, the CC’d threads, the AI-generated draft that still needs a judgment call before it goes out, all of it adds decision volume without adding hours.

The Three Kinds of Decisions Quietly Draining Your Day

Not every decision costs the same amount of mental energy, and knowing which kind you’re facing helps you decide where to protect your judgment.

• Operational decisions: The constant, low-stakes calls, like which folder a file belongs in, what order to tackle your inbox, whether a meeting invite needs a room change. Individually forgettable, but there are dozens of them before lunch, and each one draws from the same well.
• Judgment calls: Deciding what actually needs your executive’s attention versus what you can handle or hold, reading the real urgency behind a request that says “ASAP,” and choosing how to phrase something so it sounds like your executive, not you. These cost more because they require weighing context, not just picking an option.
• High-stakes decisions: Rebooking a flight mid-crisis, choosing a vendor under time pressure, representing your executive’s position in a meeting they can’t attend, the kind of judgment ODI’s World Class Assistant training is built around. These are rare compared to the other two, but they demand your sharpest thinking, and they often land in the afternoon, after the first two categories have already worn you down.

The problem isn’t any single category. It’s that operational decisions and judgment calls quietly spend down the same mental account that high-stakes decisions need to draw from later.

Six Ways to Protect Your Decision-Making Capacity

You can’t eliminate the volume of decisions in this role, but you can control when you make them, how many you make from scratch, and how much capacity you have left when it counts.

• Front-load your hardest calls. Decision capacity tends to be highest earlier in the day, the same principle behind why those parole judges ruled more favorably right after a break. Save your least reversible or most consequential decisions, like a tricky message to a board member or a real prioritization call, for your first working hour instead of your last.
• Build defaults for decisions you make repeatedly. If you find yourself deciding the same type of thing over and over, like how to triage a certain kind of email or which meetings automatically get a 15-minute buffer, turn it into a standing rule. A default isn’t a shortcut around judgment. It’s judgment you already exercised once, banked, and no longer have to redo.
• Batch similar decisions instead of scattering them. Answering five scheduling questions back-to-back costs less than answering the same five questions spread across a day between other tasks, because context-switching adds its own tax on top of the decision itself. Time-blocking techniques make this easy to build into your week: set two or three windows to process similar requests together.
• Delegate the decision, not just the task. Handing off a task while still expecting to be consulted on every choice inside it doesn’t save you anything. Give clear boundaries, like a spending threshold or an approved vendor list, so someone else can decide within them without looping back to you.
• Protect a real recovery break between decision-heavy blocks. Even five minutes away from your screen between a demanding meeting and your next task gives your judgment a chance to reset, the same mechanism that returned those judges to a 65 percent approval rate after eating. Skipping lunch to power through tends to cost more time than it saves.
• Say “not now” instead of forcing an answer. Not every decision needs to happen the moment it lands in your inbox. A short, honest “let me get back to you by end of day” protects your judgment for the decision that actually needs it now, instead of spending your best thinking on something that could wait two hours.

Conclusion

Decision fatigue isn’t a sign that you’re bad at your job. It’s what happens to anyone whose job is built on a constant stream of choices, and few roles ask for more of them in a single day than an executive assistant. Recognizing when your judgment is starting to run thin, and building a few deliberate habits around when and how you make your hardest calls, is its own kind of professional skill, one that protects your executive, your team, and your own reputation for sound judgment. If the cumulative weight of these decisions is showing up as broader workplace stress, these stress management strategies for assistants are a natural next step. The goal was never to eliminate decisions from your day. It’s to make sure the decisions that matter most get your best thinking, not your last thirty minutes of it.

Key Takeaways

Decision fatigue is the well-documented decline in decision quality that follows sustained decision-making, and it shows up as either defaulting to the easiest option or avoiding the decision altogether, not as obvious tiredness. Research on Israeli parole judges found favorable rulings dropped from roughly 65 percent to nearly zero within a session before resetting after a break, and while that specific study has been debated, dozens of others, including a systematic review showing decision fatigue effects in nearly half of assessed healthcare cases, confirm the broader pattern holds across professions.

Executive assistants face this more than most roles because the job rarely allows decisions to be batched, and it runs across three categories of cost: cheap but constant operational decisions, more expensive judgment calls about priority and tone, and rare but demanding high-stakes decisions that often land after the first two have already drawn down your capacity. Protecting that capacity doesn’t require eliminating decisions. Front-loading the hardest calls, building defaults for repeat decisions, batching similar choices, delegating with real boundaries, protecting recovery breaks, and giving yourself permission to say “not now” all work by controlling when and how often you spend your judgment, rather than trying to have an unlimited supply of it.