"Business" is translated from the English "thing."
What does it mean to "have their job?"
It means to be an enthusiastic and busy, invent and implement, "overgrown" with new contacts and partners to enjoy the results and plan to have a steady income ... Business - it is a fascinating, interesting, profitable!
But there is a downside. "To have your case" - contain office and bookkeeping, to seek a competitive product and to deliver, pay ...