In an average week, I interact with over 500 people in some business capacity. These people vary from students and professors to venture capitalists and entrepreneurs. Some I've just met. Others I've known for years. Regardless of age, stage, or profession, it constantly amazes me the little things these very different people do to sabotage their future success.
1. Grammar: This is not something to "LOL" about. Misspellings, lack of capitalization, and generally poor grammar say you're uneducated, inattentive to detail, or, frankly, just don't care. Poor grammar is like a giant fluorescent warning sign that says: "Steer clear." Please use spellcheck tools, reread your note, and if it's something "important," have others proof it, too.
2. Flaky McFlakerson: We all have our "off" moments when crap comes up, but consistently failing to show up or deliver quickly takes its toll. Chances are, you're either disorganized or a megalomaniac. Either way, it's a deal breaker. And no, your constant string of excuses doesn't help. Just do what you said you would when you said you'd do it.
3. Quick Sale: Nothing's worse than getting slimed at the cocktail party by the undercover used-car salesman. As a general rule, never ask to get before you give. Add value before you expect value in return. And for goodness' sake, please don't sneak-attack sell anyone.
4. Talking Crap: You said, "He's so annoying the way he _____." I heard, "I'm sure I'll find something annoying about you and tell everyone about it." You said, "The last company we worked with was terrible, oh, and the one before that, too. Just awful." I heard, "I'm really difficult to deal with, will be a terrible partner, and will share my misinformed opinions with everyone I meet." Unless there's a material breach of ethics involved, keep your trap shut.
5. Over-promising: Expectations matter. If you promise me a miracle, I'll expect it. If you promise me a little, I'll be happy with a little and delighted with a little more. Being impressive is mostly about being reasonable in your projections and hitting them consistently.
6. Not My Fault: We're human. Mistakes happen. But ever noticed how some people always have a scapegoat and even a backup scapegoat? The finger is always pointing in the other direction. Occasionally, another person might have played a role. Most of the time, it's your own fault. Own it.
7. Lack of Patience: I've found that nothing worthwhile comes quickly or easily. Regardless of your goals, they will take focus, hard work, and plenty of time. Stop looking for the secret sauce or the quick fix. There aren't any.
8. Pretend Motives: Actions have a funny way of exposing motives, particularly over time. You can pretend you want to help, but if it's not in your heart, it will be obvious. Think deeply about why you want something, and make sure you're transparent about it. Nothing is more off-putting than thinly veiled grabs at money, fame, or power.
9. Without Intention: Each day is packed with questions of how to spend your time, money, emotions, and focus. Do you know why you do what you do? I see lots of "ping pong people" bouncing between distractions. Pick something meaningful to accomplish and attack it. You'll be amazed at what you can do.
10. Overcommitting: You can't juggle an endless number of commitments. Every time you say "yes," you're saying "no" to something else. Eventually, things break down and blow up. Ask yourself if the commitment in question will help achieve your goals. If not, politely decline.
11. Complication: Even seemingly small choices matter. Life is packed with small corners to be cut, victimless crimes to be committed, and endless opportunities for one-night stands. Suddenly, a life that seemed so simple becomes complicated. But it doesn't have to be. Don't fool yourself into believing that this one time is different, because it's not.
12. Subtraction by Addition: When things get hard, the inclination is to do more. Work more hours. Demand more from others. In the short term, it feels great. Your brain rewards you for "doing more." But when you look back, you'll find you accomplished less. Instead, focus on addition by subtraction. Spend more time thinking, and less time doing. Be still. Be alone. Be thoughtful.
13. B.S.: Most, it seems, have a flair for the dramatic. The temperature is always five degrees warmer or cooler than the forecast. Employee count, revenue, or profits are a multiple of reality. As someone who fights this urge, I can tell you it's wildly unhealthy and quickly destroys trust. Just be honest and confident. Stop comparing yourself, and be grateful for whatever you actually have.
Confession time: I'm sensitive because I've made each of these mistakes. They're easy to make -- and even easier to keep making. Being aware has helped me, and I hope it helps you, too.
This post first appeared in Forbes.