professionals vs amateurs
Here's the definition I came up with using my own life experience:
A professional is someone who doesn't let their personal shit get in the way of getting work done. If something needs to be done, you can trust that a professional will get it done, one way or another.
Work can mean be posting a blog, taking a sales call, interviewing a candidate, writing code, launching a marketing campaign, presenting a seminar, creating a presentation, painting a portrait, sculpting a clay pot, or kicking a football.
And of course there will be extenuating circumstances, but they will still get the job done. If they're sick, they'll delegate the work to someone else and give them very clear instructions. Or they've prepared for this situation beforehand and have already finished the work.
Work is about serving others. That's why a true professional will never let his personal problems impede completing the work. It's not easy, but it's what we should all strive to do, no matter how insignificant our jobs or responsibilities are.