Why did settlers expand westward despite the challenges of the physical environment

The reason why settlers expand westward despite the challenges of the physical environment was: they were hoping for a better life.

Despite challenges of the physical environment, the settlers were promised that they would be given a really chip set of land that they can use to open new businesses. People from various corners of the world heard this news and decided to try out their luck in hope for better life.

the exclusive possession or control of the supply or trade in a commodity or service.