People do not develop in isolation they are shaped by the world in which they live and grow.
There are so many factors that can influence a person’s character and beliefs, such as:
- their family background and structure,
- social class,
- available opportunities,
- encouragement and ridicule from peers and family,
- how they were raised and by whom,
- their friends and how they were raised,
- outlets for their talents and skills,
- subjects chosen to study,
- the politics and structure of the society they grew up in,
- whether they grew up in times of peace or war.
All these things should be considered when developing your own characters for your writing. Everybody is different. It is what diversity is all about.
I often spend hours creating character sheets about my characters and not just the main protagonist. I want to know everything about them and I think how these things would influence what they say and how they react. It is more than just jotting down their physical detail.
My writing group once laughed at me when I showed them my five-side character sketch for my main protagonist.
After I have developed the character I try to think of scenarios (not necessarily to do with the story I am writing) and jot down how they would react if they were angry, happy, sad, etc. I really want to delve into their mind, know what they are thinking and how they would phrase things in different states of mind.
Try it for yourself and see what happens.