What in your view makes a good photographer?
This seems to have turned into an "essay" as your question reflects something I have been thinking about a lot recently. What makes a good photograph? So although I have dramatically truncated my thoughts, and I am still working on it, here is my rather long answer.
I like the shorter definitions that have already been offered , and would go with:
"A good photographer is a person who regularly makes good photographs"
But, I want to deconstruct this a bit
I have very deliberately used "make" photographs rather than "take" photographs, because this implies intent and purpose to the photographs, which better connects "good" photographers to "good" photographs. than "taking" I've also used "making" photographs to help define photographer as I don't think a photographer is just "anyone" who takes photographs.
Just writing out shopping lists with a pencil, or using a word processor to write letters doesn't make someone a "writer", and similarly everyone that takes a photographs is not a photographer. So I am excluding the millions of people who take billions of photographs every day of their cat, their breakfast, their child looking cute, a holiday sunset, a majestic view from their hotel bedroom, themselves and the multitude of other subjects recorded every day as digital mnemonics. That is not to deny the value of these images, I just don't believe they show the level of intent or the emotional and intellectual commitment to the photograph, that would justify the taker being called a photographer.
I have used "regularly" as it implies "often, but not always". Even the best photographers have days that don't go well, but on balance, most of the time, good photographers produce photographs somewhere between "fit for purpose" and "good", with the occasional "better than just good". Regular also takes on different meanings depending on circumstances. A good wedding photographer needs to produce, at least "fit for purpose" photographs every time. A good wildlife photographer, may have many days that don't produce any good photographs at all. A "fine art" photographer may only produce a dozen or so good photographs a year.
Taken together "make" and "regular" excludes the "lucky" shot. An occasional good photograph isn't enough to make someone a good photographer. An example of this might be photographs taken for scientific purposes, by a scientist, where some turn out to be spectacularly good photographs because of the subject matter, that may even win a photography award, but that doesn't make the scientist a good photographer.
Which brings us back to what is a good photograph, which is a question I ask almost every day.
For commercial work, the photographer will have the primary intent of making photographs that meet the requirements of the client. How good the photographs are will be primarily judged by client and photographer. How good the photographer is can be assessed by repeat business, industry awards etc. There are however nuances to this as many professional photographers have a much deeper connection to their art than commercial success, and their own judgement of how good their photographs are might be based on very different criteria.
For non-client directed work, which could still be paid for (ie through grants, stock photographs, selling fine art prints etc), but is more often personal work, where the intent is almost entirely driven by the photographer, assessing good is more difficult.
I have found it useful to use the mirror and window concept, where some photographers want to open a window on the world to share something you might otherwise not have been aware of. While for other photographers their photographs are mirrors reflecting their inner feelings about their place and interaction with the world, often more abstract, bizarre and difficult to understand. But, to continue the allusion, just as windows can also reflect light as well as transmit it, a good photograph is probably one that is both window and mirror, that demonstrates an obvious intellectual and emotional commitment from the photographer, and triggers an intended emotional and intellectual response from the viewer.
A good photographer is therefore someone who can regularly produce this type of photograph.