iPhone 6s home button sensitivity ?

Hi all,

This is the first time using an iPhone so just wanted to know that how much should I press the home button for going to the home screen, should I press it lightly or should I press it till I hear the click release sound. My friends say that my iPhone 6s is faulty as I have to press the home button fully till I hear/feel the click to minimise any app I use or just to go to the home screen, but I feel their iphones home button requires only a slight touch with minimum pressure for the same.