From millions of anecdotes about "pushing through", "putting in time", "paying your dues", to "earning your stripes".
Over the past 20 years I've been insulted, yelled at, stolen from, scammed, tricked, lied to, pushed against a wall, and kicked. So yeah, running a business can be hard.
Luckily, these kinds of confrontations don't happen very often and I have gotten much better at reading the signs of a bad client earlier in the process. The most important skill in this respect is how to tell the difference between a bad client, and a good client who's expectations aren't being managed correctly.
It is not new, it is as old as creation itself. Centuries ago it was expressed this way: "Whatsoever a man soweth that shall he also reap." - Col. Wm. C. Hunter, Dollars and Sense, 1906
Bad clients are generally unsatisfiable. They expect everything for nothing and don't appreciate any of the work being done. A bad client doesn't bother learning anything about the craft, the language, or how it effects them other than to act as a target for complaints. They see no value, yet treat every error or problem like it's the end of the world.
A bad client thinks we should do all support for free and demands refunds even though deposits aren't supposed to be refundable. In other words a bad client is bad for business. Some of you might think there are no bad clients and that even what I've described above can be managed. I won't argue with you, you can have them.
Now let me speak a little about the clients I appreciate very much. They are the perfect counter balance to a bad client and I can't praise them enough they have been so good to me. They are the honest ones; fair, communicative, kind, pay well, and thank me for my work. When things aren't happening on a predicted timeline, there's no yelling. Just clear professional discussion on how to improve measurement and communication with their staff.
They are the ones that taught me how to formalize the expectation process so I could improve my tools to keep the developers and the client team synchronized. That's a partner. A client who understands the potential of working together and the value of people. It's because of the good clients that I keep doing this.