In early 1997, just out of law school, I turned down a good offer from a prestigious firm to start my own with a friend.

We didn't have much by way of experience, managers, or mentorship, so we had to figure it out on our own. I would manage practical things like office supplies and the accounting system, and my more sociable colleague Brent brought in the clients.

So I bought a thin paperback book on how to run a new law firm.

"Don't take a bad client just because you need more clients."

That was the best advice from the book, and something I pass on to every professional, whether they're an artist, management consultant, or a construction contractor. It is also true in most industries about customer relationships.

Everyone has a horror story, it's just not worth it.

These are the clients who are extra demanding, who don't take advice, get into arguments, bring personal drama, leave a trail of mayhem and legal liability, who don't pay or try to renegotiate the bill after you've finished all the work.

The other thing the book said was this:

"I give you this advice, but you will have to learn this for yourself."

Also true about most everything, everywhere.