Pursuant to CPLR 3215(f), an applicant for a default judgment against must submit proof of service of the summons and complaint, proof of the facts constituting the claim, and proof of the defendant's failure to answer or appear. In order to demonstrate the facts constituting the claim, the movant need only submit sufficient proof to enable a court to determine that there is a viable cause of action. In order to successfully oppose the motion, the defendant must provide a reasonable excuse for the default and demonstrate the existence of a potentially meritorious defense to the action. Whether a proffered excuse is reasonable is a sui generis determination to be made by the court based on all relevant factors, including the extent of the delay, whether there has been prejudice to the opposing party, whether there has been willfulness, and the strong public policy in favor of resolving cases on the merits. The determination of what constitutes a reasonable excuse lies within the discretion of the motion court. Where the defendant fails to demonstrate a reasonable excuse for its default, the court need not consider whether the defendant possesses a potentially meritorious defense to the action. Defaulters are deemed to have admitted all factual allegations contained in the complaint and all reasonable inferences that flow from them.
Cartessa Aesthetics, LLC v. Demko, NY Slip Op 03328 (2d Dep't June 21, 2023)