Why people who does love marriage keep an extramarital affair?

Now a days the extra marital affair can be heard the second hose in neighborhood and one gender is not responsible for this sometimes a man caught with another women or a women caught by another man here are some of the reason why people are indulge with extramarital affairs are as follows:

Becoming parents in an early age.

Early marriage can be the reason.

Physical dissatisfaction.

These are some of the reasons for extra marital affair.