Choreography is a very personal thing, but to who? The choreographer or the dancer? The answer is both, in my opinion. While the choreographer draws on life experience to create a piece it is also very important that they are choreographing and catering to the needs of each individual dancer. This includes movements that are age-appropriate, level-appropriate, to prevent injury as well as how the choreography sits in the dancer's body.
When creating a piece of movement it is important to highlight the dancer's strengths and play down the weaknesses. When this is done correctly it shows up on stage. The dancer is comfortable, therefore dancing and performing better and the beauty of the choreography can really shine through.