One reason why mountaineering can be so dangerous is because of The Sunk Cost Fallacy: the idea that just because you've invested time and effort in something that's reason enough to stick with it. Once you've traveled a long distance it's easy to downplay obstacles like bad weather or slow progress.

In 1996 eight people died during a trek to the top of Mount Everest; that's why mountaineers have started using stop rules to ensure they get home alive: for example if we haven't made it to checkpoint d by 3 pm we turn around, no matter what.

Establishing terms like these force them to override the emotions that arise in the heat of the moment.

Personally i won't be climbing the world's tallest mountain anytime soon but i do employ stop rules or hard stops throughout my work day; having them in place boosts my productivity and keeps me focused on my goals.

One strategy i recommend is Time-blocking: the process of blocking off time on your calendar to work on your most important projects. It saves you from a common trap of administrative creep, which happens when innocent looking tasks such as responding to a message on Slack or quickly processing your email inbox take much longer than expected.

Before you know it the best hours of your work day are gone and you don't remember what you spent them on.

When you start each day by blocking off time for at least one important task two things happen:

• (1) You activate Parkinson's Law which states that work expands to fill the time available for its completion. You'll somehow find a way to get all the administrative stuff done in the time that remains.
• (2) Your focus will improve. Planning your day makes it painfully clear just how little time you actually have. That's a good thing because you understand what's at stake as a result you take your time block seriously: you turn off notifications, close your office door and focus on that one most important task to get it done.

Stock traders often set hard stop rules like "if the stock price drops more than 10 percent i'll sell immediately". This prevents the sunk cost bias from pushing them to hold on too long; it allows them to act fast and minimize losses by preventing a drawn-out analysis while prices drop.

Our productivity can be like stock prices: we often keep telling ourselves that we'll improve tomorrow but have no clear thresholds to trigger action.

Hard stops help us focus on the work that matters and protects us from one of our biggest roadblocks: ourselves.