When you work with asynchronous JavaScript, errors can appear in ways that are different from what you might expect with synchronous code. Some of the most common error scenarios include missing error handlers, unhandled promise rejections, and issues that arise when asynchronous operations do not complete as intended. For example, if you forget to add a .catch handler to a Promise that might reject, the rejection can go unnoticed and either crash your application or result in a silent failure. This is especially problematic in production environments, where silent errors can be difficult to trace and fix.