What is a reason that species becomes extinct?

Animal extinction is caused by humans, everybody knows that. The top reasons are habitat destruction, and hunting to sell body parts, like tigers for their fur and bone.

I think habitat destruction is the top main reasons because it has more consequences over time since most animals will be unable to recover that space. There are also people who capture animals, to sell them later on to wealthy people who have nothing else to do with their money, but to buy endangered animal species, to illegal shows or circus e.t.c; So you understand, the main reason for animal extinction, is human intervention on their natural life, and environment.
1. Human Hunting 2. Habitat loss

3. global warming

4.starvation

1. Increased Competition

2. Change in the Environment

3. New Predators

4. New Diseases
Mostly habitat loss and over hunting are the main reasons, poaching endangered animals such as tigers.
Survival of the fittest. They lack the ability to gather enough food to survive, or to live in the conditions they are in.

This can be from something such as their food source being taken away or their habitat changing very quickly due to a natural disaster. Also they can be hunted to extinction by people.
What are the reasons for the extinction of species