Answer: A thesis acts as a sort of sample for what the entirety of your essay is about | the claim or point you are trying to make.
Step-by-step explanation:
It is common to hear that one should write their essays in a way so that the reader with absolutely no knowledge, is able to: not only understand the context of the paper, but also come to an agreement to the point/claim/rebuttal you are trying to make.
Despite its importance, a thesis is usually located in the last sentence on the introduction indicating that this is a scenario that involves quality over quantity.