What kills happiness? Sometimes it’s a big thing; but it’s usually a series of little things that pile up over time.

For instance, saying yes too much when you should really be saying no. Have you ever heard the old saying, “If you want something done, ask a busy person?” It makes sense. It’s obvious they are able to get things done. But there is a fine line between taking on a lot and taking on too much.

People in corporate situations often fall into this over-commitment trap. It’s easy to see why. If you like what you do and you’re good at it, it shows. Everyone wants you to be at their meeting; they seek out your opinion; they ask you to run a project for them. Busy people find no shortage of opportunities. And, this happens at all levels. It’s how junior employees advance more rapidly than some of their cohorts. Their ambition and enthusiasm is contagious. Their bosses pile on the work – the employees don’t cry uncle (until it’s too late). And that’s when their work quality deteriorates and they begin to falter. It’s a predictable and vicious circle.

Self-employed people really fall for this happiness killer. That’s because without the cushion of a steady paycheck, every opportunity could be the last. So, you take on everything even though it’s impossible to do it all. I do this. As a speaker, I show up for the day, share my knowledge and get paid for my time. It’s a straightforward pay-for-work opportunity. If I show up, I get paid. If I don’t, I don’t get paid. I look at unbooked periods as valuable time during which I can catch up on my reading and writing, or simply relax with my family.

Then someone will want to hire me for the day. I’ll say no at first, because I’ve planned to do these important things. But often they’ll persist and I soon find myself saying yes to a gig a few months away, rationalizing that who knows what the economy or my future bookings will look like, I’d better take what comes. Really, though, I might be better served to say no and write my next book! I’m lucky to have this problem. And, I know that if I say yes too many times when I should be saying no, the feeling will compound to dangerous levels and will turn into burnout.

That’s the lesson of the #1 Happiness Killer. For those of us who tend to over-commit, we have to watch out. Over-commitment is liable to make our spirit sag on the inside and soon will become obvious on the outside to everyone else. Our great job will turn rote, our execution sloppy and apathetic. It will make us appear under-committed, and this is rarely appreciated by our customers or colleagues.

Practically everyone feels over-committed on occasion. It’s a hard thing to admit for lots of reasons. Maybe we don’t want to look like we can’t handle the challenge. Maybe we want the validation of being told we’re doing a good job. Maybe we think that taking on too much is no excuse for dropping the ball.

The key is before you reply with another enthusiastic “yes” to that request, think of the long-term impact it will have on you. Is it right for you in the long-term? Are you just saying what will make others happy in the short-term? And, is what you are about to commit to going to increase the longterm happiness and meaning that you experience in life? Or not? The answers will help you avoid the #1 Happiness Killer – over-commitment.