During a time when the boundaries between our work and our personal lives feel tenuous at best, multitasking feels like a natural solution. Multitasking at work often involves attempting to complete two cognitively demanding activities simultaneously.

The ability to switch between tasks often makes you feel like you’re getting a lot done, but several studies have shown that this constant routine of switching gears isn’t an effective way to make progress and can take a toll on our brains. Not only can this habit sap your energy, but constant multitasking can make it seem more appealing, creating an addictive cycle.

There may be times where you’re opting to do multiple tasks simultaneously when it’s actually the less efficient choice. Understanding these three common multitasking myths can help you manage your time more productively:

You feel a sense of accomplishment, so you must be getting a lot done. Hate to break it to you, multitaskers: This feeling of accomplishment is a false sensation.

Multitaskers often get addicted to this cycle of small-scale accomplishment (and usually executed at a suboptimal level) without realizing they are spending more time completing their work than if they had chosen to stick to one task.

The singular approach is called monotasking—which means cutting out the jumping around and focusing deeply on just one project.

You save energy by switching between tasks. The truth is that when you force yourself to shift from one mentally taxing job to another, you are not only wasting time but also draining your energy reserves.

Moreover, when you quickly pivot to the next “to-do” item, you leave the phantom-like presence of the last task in your thoughts. This is called “attention residue,” which is as unappealing as it sounds. Basically it’s the idea that although you have moved on to your next task, your brain is left contemplating the previous one.

You get better at multitasking the more you do it. Fast Company reporter and editor Lydia Dishman confesses to being a reformed multitasker. While working to wean herself off multitasking, she realized that it was a much more difficult habit to cut out.

We can only successfully perform simple, rote tasks when multitasking. As Fast Company contributor Art Markman points out, nonchallenging, intellectually simpler tasks are usually okay to juggle at once; these are often habitual activities that tax the working memory.

But for more demanding, complex tasks, it’s important to direct your best self toward these efforts, or suffer the consequences of poor performance.

If you are attempting to complete two tasks at once, it’s a far-fetched idea to think both will result in fantastic work. Says Markman, “You’ll likely get worse at both of them.”