From 16 to 18 add pumping gas, and restaurant kitchen work.
All thru college, waiting tables, tending bar, and cooking line in restaurants.
Then right to full time job after college, married the following October. My kids all the approximate same progression and work ethic. Last one graduated a semester early with a full time job in software engineering in the company's London, England division.
Work ethic is a trait from home.
I worked for 79/cents per hour washing dirty cooking pots in a hospital kitchen in 1961. That was my first job, while working on my master’s degree in engineering. It was good because I could eat in the employee cafeteria for 39 cents. Saved me buying groceries and cooking.
Work ethic is a trait from home.
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Work ethic might be the most important trait.
Both my wife & I have huge extended families, so I tell every youngster one thing:
“Always be working to maintain your cash flow.”