There are artists that have style and there are artists that do not have style.
Style comes from experience in one's profession. For example, THE BEATLES. Did the Beatles have style? Yes they did and they became so good that they were able to change their style.
When you hear a Beatles tune do you recognize that it is the Beatles? If you hear early Beatles music you, most likely, will recognize the style of the early Beatles.
What made the Beatles so good is that their style would change as the years changed. If their style never changed, it is quite possible that they would have lost popularity many years ago.
Have you ever read a book by an author then by chance picked up another book by the same author and noticed that the style was the same? Some author's styles change very little. Others change their style as they grow and progress.
It is the same with photographers. You will see a certain style with particular photographers. However, with some photographers you may not see a style change, while others never develop style.
An artist, and I include photographers with the artists, should be able to recognize their own style.