تعريف ومعنى "[mix] business with pleasure"

What is the origin of the idiom "mix business with pleasure" and when to use it?

The idiom "mix business with pleasure" refers to the act of combining work or business activities with leisure or recreational activities. The term is often used as a cautionary phrase to advise against engaging in activities that blur the line between work and personal life, and to emphasize the importance of maintaining a professional demeanor in business settings.