Recently I was playing golf (badly), and a very successful salesman in my foursome hit a terrible shot and said, "Anyway, a bad day on the golf course is better than a great day at the office." I laughed, but inside I really felt sorry for the guy, because I could not imagine hating my job that much.

So, why didn’t the sales guy quit? One answer: He earned great money. Is it worth it staying at a job you don’t love if you’re earning great dollars? In my view, whether you are young or old, only focusing on earnings is a tremendous career mistake for a few big reasons:

Chase your passion.

Many of the most successful businesspeople in the world have said they would work at their jobs even if they did not get paid. Why? Because they had so much passion, their careers did not seem like work -- they truly enjoyed what they were doing every single day. 

Ironically, this strategy is also the best financial decision: The more you love something, the better you will be at it, and the more money you will end up getting paid. This is true whether you are a startup CEO, a ballet dancer or a surgeon. Beyond this, we all know nothing great comes easy -- so do what you love and you'll also be more equipped to deal with inevitable setbacks without getting despondent.

Play long ball.

If you are lucky enough to love your job, or your industry, don't even think about changing careers just to make a few extra bucks. I see so many young people leave jobs they love because of deluded short-term thinking. I worry that many of these people will end up very dissatisfied in their mid-40s or 50s and wish they had stuck with what they were really passionate about. Remember, your career is going to last decades -- short-term monetary gains are small battles, but long-term career satisfaction is the war you need to win.

Know yourself.

One reason that many people don't work at a job they love is that (believe it or not) they have no idea what they love. We live in a fast-paced world, and it's hard to throw your feet up on a desk and just reflect on what gets you excited and inspired. I encourage everyone to get to know yourself, cultivate interests, read books and if you can afford it see a professional coach or a therapist. You're only going to get what you want once you know what it is.

It's about the journey.

I have friends who sold the business they founded and loved for huge money, but who became miserable after they stopped working. Why does this happen so often? Because money, like so many other superficial things in life, is a means to an end and does not bring happiness. One of the wisest sayings I try to follow is the value of achievement is in the achieving. It's the journey you absolutely need to enjoy, because the destination (e.g. the big bonus at the end of the year, the IPO, etc.) will never live up to expectations.