I like doing bird photography for many reasons.
It pushes me out of the house and into nature. It is a great way to be close to nature, to treasure it. Birds are these fantastic creatures: the dinosaurs that survived a mass extinction, adapted and thrived after the disaster.
The hunt is fun. You must get close; you must become a predator that doesn't kill but instead takes shots with a camera. You must move around, wait, and find the right angle. Be patient. I think this is a great complement to my own meditative approach to photography.
There is also a part of me that is a tech geek, and bird photography has a lot of that.
The subtle balance between having the right or good enough gear, but at the same time, something that is affordable (not some crazy $20k in camera + tele), and that you can also reasonably carry.
I love the tricky technical aspects involved in photographing birds. You do have to think on the right settings, the right technique. Some of those small details can improve your success rate a lot.
Bird photography also teaches you to lose (but I think this is a general aspect of photography in general). You may see a great opportunity for a shot, an amazing bird perched in the right place under the right light, but if you are not ready, don’t have the right lens, the right settings and don’t do act quick enough… you are out of luck. You lose your chance, and that image will only live in your mind.