The 8 Dumbest Career-Ending Mistakes That Smart People Make  (Forbes.com)

 

1. They assume their past success will continue in the future on new projects.  There’s an arrogance that can take hold in really smart people over time.  They’re used to being the stars.  They’re used to having an audience of admirers.  Their whole lives have been a series of one success after another.  Why wouldn’t this pattern continue, they think?  This over-confidence breeds lots of blind spots.

2. They stop paying attention to details.  When you have success early in your career, you get promoted and you get further opportunities to show your skills.  Quite often, you get more responsibility too.  If you’re over-confident that your past success will continue, you can stop paying attention to all the details like you used to during the early times when you had some of your biggest successes.  You can start mailing in your efforts, or you simply delegate the details to others and forget to check up on them later.  Because you’re still so busy, you don’t realize everything that’s slipping through the cracks beneath you.

3. They forget their own strengths and weaknesses.  Let’s face it, none of us is perfect.  No matter our college degree or education.  No matter our latest achievement, we all have strengths and weaknesses.  The most successful people in the long-run never forget their weaknesses when they look in the mirror.  They find a way to surround themselves with people who can cover those weaknesses because others have strengths in those areas.   The smart folks who fail assume they can be experts in areas that they have no business offering opinions on.

4. They banish people from their inner circle who have a different opinion.  Nobody likes to be told they’re wrong.  At the early stages of our careers, if our boss tells us we’re wrong, we have to accept it.  As we grow into positions of authority, someone tells us we’re wrong, we can simply tell them they’re probably not the best fit on our team.  Over time, the smart people who make dumb mistakes surround themselves with “yes” men or women. They assume – based on all their past success – that they can’t be wrong.  And they will drive full-steam ahead on one of their decisions, even if it drives the whole company off a cliff.

5. They forget that you catch more flies with honey than with vinegar.  There’s an old saying: “be nice to the people on your way up, because you’ll also be seeing them on your way down.”  We all have highs and lows in a long career.  At some point, no matter how successful you are in the moment, you will get knocked down by something or someone.  And then you’ll need allies and supporters.  Therefore, don’t alienate people by telling them how brilliant you are and stupid they are — even if it never seems like you’ll need their support in the future.  You never really know who you might have to call on for a favor in the future.

6. They decide to move out of their area of expertise.  Sometimes on business TV, you’ll hear people quoting how so many big mergers or acquisitions have ended up destroying value instead of creating value.  We might be successful because we know the business we’re in but that doesn’t mean we can now know every other business under the sun.

7. They don’t build bridges with all the senior people who will have a say in their fate.  A lot of times, smart people assume that their results will speak for themselves.  But we live in a world where relationships matter.  It’s not just in Game of Thrones where good guys get their heads chopped off out of nowhere thanks to some enemy they never realized they had. It’s again arrogance to think that your brilliance and successes will speak for themselves.  They might have just the opposite effect of annoying some key influencers above you who think you’re full of yourself and not ready for the next big promotion.  You’ve always got to be selling yourself to others to ensure they know your success and abilities (although you have to do it in a way that doesn’t annoy those above you).  It’s got to be sincere, not obsequious.  Who’s going to do your PR if not you?

8. They take needless risks in their personal lives.  One final word of warning: if you think you can be the top of your game in your work life and have one vice in your personal life that won’t affect it, you’re probably very wrong.  Whether it’s gambling, alcohol, drugs, adultery, or something else, you’re playing with fire if you can’t control yourself in those areas.  Sure the politicians like Anthony Weiner, Gary Hart and John Edwards come to mind, but there are lots of smart and successful engineers and other professionals who succumb to this one as well.