As photographers, before we knew we could, we on occasion could produce good shots but they were flukes. Maybe even great. A bit of luck. The cameras settings seemed to be all perfect, the timing was perfect, that perfect expression or environmental elements. A magic moment. An image that produces pride. The "I shot that and it's fucking awesome!" feeling.
The next 50 frames or 5 shoots are shit. Expect that as you improve. The ratio will eventually reverse and instead of 50:1 you will start hitting 20:1 and maybe somewhere closer to 5-10:1. I don't know anyone that is 1:1, that is 1 click 1 good shot. If I had to judge my clicks to usable good shots, probably 1:8 or maybe 1:5. As for a "great" shot, well that I guess is subjective but maybe 1:25 or so - bear in mind that I shoot people and many good and even a few great shots were screwed up by things outside of my own ability such as blinks or flash didn't fire or something stupid.
It's when you hit a consistency of good and awesome that you are a photographer. A real one. Not a fake one. Not a dude who happens to have inherited or purchased their toy a few months ago. Don't get me wrong, you can call yourself a photographer the moment you pick up a camera. But there is an invisible ranking, probably no one will say your stuff is shit in the beginning, you will probably get lots of encouragement. We all start at the bottom. Don't be content with the bottom (or any plateau on the way up for that matter).
This is the #1 factor that determines and decides whether a person is a good or professional (not in a "monetary business " sense but an "ability to do" sense).
The rest of these are flanking attributes which go into "Consistency".
2) Ability, willingness and persistence to overcome obstacles.
Whether you enjoy shooting people, nature, bugs, airplanes, weddings, products you will always encounter barriers and obstacles. This is true in every walk of life you are pursuing. Exercise, other forms of work, being healthy, going on vacation. Imagine a life where there were no barriers or obstacles? How boring.
But you must persist and be willing to endure whatever shit heap is thrown at you. Sometimes it's yourself, sometimes it others. Sometimes it's the material world (car breaks, camera breaks, it rains, it's too hot, no money, no time, you name it). Don't convince yourself that the barriers are bigger or cannot be passed in some way. This is important.
Obviously, you've got to be familiar with your medium. Not only physically, such as with cameras, the physical buttons and where they are but also the significance behind each part and button. Then it's knowing the effect each has and finally how you can manipulate and challenge these things and channel it toward your vision.
Let's take a real simple cause and effect look. Hitting a target at 1000 yards with a 9MM is near impossible. Nearly. I KNOW that I cannot. I can guarantee though that this guy KNOWS his guns and this particular one. He also has practiced, a shit ton. Thousands of hours and tens of years. You can do this.
Have a look.
Another book I was turned onto recently is Outliers by Malcom Gladwell. According to this it takes 10,000 hours to hit that sweet spot of being really good at your medium. I mean, really really good. Build on that and you get even better. Worth a read or listen.
4) An ability to communicate.
Life is all about this. We get through problems so much easier when we communicate with a good listener. Our art is a communication; a photograph, song, movie whatever. There is probably a direct correlation between one's ability to communicate properly and with relevance and intelligence and one's potential income. Just a thought.
What are you trying to communicate? What detracts from that message, what aids it?
In everyday life, I think communication done right can help people to overcome barriers and obstacles. If you can't communicate well, it's a lonely world to overcome on your own and being misunderstood all the time just sucks.
Finally, there are many other traits which are important and flanking. Such as knowing some of the history of your medium. Understanding the mechanics of light. Being able to observe and having some imagination. Since a "good" photograph can be somewhat subjective, it's capturing things in a way as to capture the attention of your viewer (watcher, listener, etc) later. Thinking outside of the cliche (aka the box). Having an interest in your subject. Researching your subject prior to shooting it. Having a style. Having the right gear for the intended effect (or figuring out how to get by). Finally, knowing something about how to retouch your images to complete your vision. There are probably more but you get it.