The pursuit of productivity has become an obsession, with no shortage of advice available for how to increase one's output. Similarly, advice on how to avoid habits that result in the opposite are hardly in short supply either. That's why the advice of former clinical psychologist and author, Alice Boyes, published in a recent Harvard Business Review, really caught my attention --it focuses on simple mental mistakes you make that undo your proclivity for productivity.

Sometimes the things that derail us are right under our nose, things we control that have a nasty cumulative effect, like that of simple mental miscalculations we make and their effect on our productivity.

Being a former senior executive in corporate and now a successful entrepreneur, speaker, and author, I can tell you as much about productivity blockers as boosters. What I share now blends the best of Boyes' advice along with my own experience for preventing the mental errors we make that tank our productivity. Your awareness will lead to your avoidance.

1. You think you have more focused time than you do.

I used to continually fall victim to this. The core of the issue is that we underestimate the number of interruptions we'll get during the day. We'll check our iPhones for the fourth time in the last half hour because we subconsciously don't feel like thinking and buckling down. We reason that's okay though, because there's plenty of time to focus remaining in the day.

And it just doesn't turn out to be true.

The solve is to be realistic about how much heavy concentration time you'll really have and to use that realistically shortened window as the prompt to be brutal about prioritizing the most important thing or things to accomplish.

2. You think you're a good multi-tasker.

Guess what? You're not because no one is. Multi-tasking isn't even an actual thing and from my experience, it's the biggest mental mistake of all in terms of wasted productivity. Multi-taskers create the illusion of productivity because they feel good about their habit but are actually less likely to be productive.

Earl Miller, professor of neuroscience at MIT, dismissed the myth of multi-tasking in a seminal 2008 interview with NPR, saying that we simply can't focus on more than one thing at a time. Period. But what we can do is shift our focus from one thing to the next with astonishing speed, a phenomenon known as task-switching. But it turns out that speed kills. Says Miller, "Switching from task to task, you think you're actually paying attention to everything around you at the same time. But you're actually not."

In fact, with task switching, your brain is forced to switch among multiple cognitive tasks as these tasks use the same part of the brain. So literally and brain-science wise, you can't do two things at once. So stop making the mistake that you can and develop a habit of single-tasking versus multi-tasking. 

3. You think you can do everything by yourself.

This was the first productivity lesson I learned when I became an entrepreneur. If you want to be maximally productive you have to learn to delegate or farm out tasks to someone else who is better suited to them than you are.

Bringing a business manager and project manager on board to my company were the smartest things I ever did. Too often, we burn productivity by trying to handle too much, too often. Don't fall into this trap.

4. You mentally dismiss the basics.

Boyes indicates we're too likely to skip proven, sustainable productivity tools we can implement. Things like to-do lists, ending the day by making a plan for the next day, removing your phone from your workspace during crunch times --these are all things that aren't sexy. So we blow by them in search of a bigger wholesale change to implement. There isn't one. Productivity enhancement is a series of incremental small steps that lead to big change.

5. You underestimate a break in flow.

Those little stops you make to check your phone are more harmful than you think. Noted psychologist Mihaly Csikszentmihalyi teaches the concept of flow, getting into an enjoyable mental state where you're maximally productive, in a rhythm, and producing at your peak. Breaking flow is a big deal. Don't.

6. You think taking plenty of breaks tanks productivity.

Don't be confused by number five above. You should take breaks. In fact, the Pomodoro technique, which I use to great effect, says work in 25-minute blocks (using a timer if it helps), followed by a 5-minute break. Most people think productivity comes from marathon sessions, not so.

Improving productivity takes effort so you don't want to unwind progress you're making with mental mistakes. A little mindfulness will go a long way.