Biological causes:

Experts believe a number of biological factors may contribute to quick ejaculation, including:

Abnormal reflex activity of the ejaculatory system
Weak PC Muscles (pubbocoxygennus muscle)

Psychological causes:

Some doctors believe that early sexual experiences may establish a pattern that can be difficult to change later in life such as:

The Techniques which you use during love making,
Inability to apply or use any ejaculatory delay method,

Risk factors :

Various factors can increase your risk of quick ejaculation, including:

Stress: Emotional or mental strain in any area of your life can play a role in quick ejaculation, often limiting your ability to relax and focus during sexual encounters.
Certain medications: Rarely, drugs that influence the action of chemical messengers in the brain (psychotropics) may cause quick ejaculation.