How to tell if a turbo is gone?

For those unfamiliar with the intricacies of automotive engineering, determining whether a turbocharger has failed can be a challenging task. The telltale signs, however, are often quite evident if one knows what to look for. Common symptoms include a lack of power or acceleration, a surge in exhaust smoke, and perhaps even a rattling noise coming from the engine bay. Additionally, the turbocharger itself may exhibit visible damage such as cracks or oil leaks. Regular maintenance and inspections can help catch potential issues early on, but ultimately, a professional mechanic's diagnosis is often the most reliable way to determine if a turbocharger has indeed gone bad. Can you elaborate on some of the specific warning signs that might indicate a failed turbocharger?