Theists: What is the most compelling argument you have heard for Atheism?

[Neo-Scholastic]

For theists, the existence of a Necessary Being is strongly suggested by the apparent contingent features on which the the universe seems to depend. The skeptical objection to our stance, appealing to chance, is quite odd and is really just a way for them to have their cake and eat it too. That approach allows the skeptic to acknowledge the contingency of the physical world while tacitly relying on "laws of chance" that must transcend the universe in order to constrain its possibilities. This is just another way to bring a Necessary Being in by the backdoor while expressly denying there is one. The other skeptical objection is to consider the features of the physical universe brute facts, a simple assertion that some facts about the world are not subject to the principle of sufficient reason.