This refers to the things you make. Your products. Your work.
—If you’re a salesperson, it’s your level of expertise with the thing you are selling. It’s your high EQ and your ability to connect with people, solve complex people problems, and close deals.
—If you’re a teacher, it’s your domain knowledge and educational methodology.
—If you’re an engineer, it’s about how well you can build systems, identify bottlenecks, troubleshoot issues, and configure results.
—If you’re a waiter, it’s the standard of your customer service. How many people you can serve and the quality with which you serve them.
This is your process and personality.
—What’s your approach?
—How do you manage your time? Work within constraints?
—What’s your attitude?
—How do you respond to criticism or praise?
—How do you work through problems? Deal with stress? Make friends and influence people?
—What unique flair do you bring to the job?
People don’t always remember the work you do, but rather, how you made them feel. Substance is important. It’s what helps you progress, get better jobs, and build something you can be proud of. But the style in which you do it is what people talk and write about.