Actually, in thesis statements, you never ask 'why'. The entire purpose of thesis statements is to argue something. you branch your perspective of the question out and expand it briefly. That is your thesis statement.
Journey broadens one’s understanding of themselves and the world around them, through influential and key experiences. It is essential to the human condition to undergo a journey even one as simple as life.
This thesis was used in my introduction on the poem "At Mornington" by Gwen Harwood