A professional is able and willing to perform in any situation. An amateur is not.
Let’s look at photography, which is something that I don’t know a whole lot about but I think I know enough to use it as an example.
The technology in today’s phones let anyone take fantastic pictures given the right circumstances. And because we always have a camera with us and it costs us nothing to take as many pictures as we’d like, it is so easy to find those right circumstances. But that doesn’t make everyone a professional photographer and it definitely doesn’t diminish their work.
The difference between the amateur and professional photographer is that the professional can deliver when the circumstances aren’t just right. She knows how to position her subjects so the lighting is right or how to control the aperture to brighten the picture some. She has the tools on hand – a tripod and extra lighting – that allow her to make the imperfect situation work. If she’s good she’ll get inspiration from that imperfection and her work will be even better.
I am not a professional photographer. I can rig up a temporary camera mount so I can take pictures on a delay. But I don’t know how to fix the problems I see when my subjects look too flat. I’m an amateur.