A pretty serious case of screen burn-in on an iPhone 15 Pro Max
Burn-in often starts as image retention. This is a ghost image showing a previous screen that will go away over time. So if you have image retention on your iPhone, turn off the device before it turns into a case of permanent burn-in. Some apps that are static for a long period of time, or with screen elements that don’t change, like Google Maps for example, are prime candidates to contribute to screen burn-in.
Yet another case of screen burn-in on an iPhone 15 Pro Max
Even so, it does take a long time for screen burn-in to take place which means that the iPhone 15 Pro Max screens exhibiting this issue might be suffering from a manufacturing defect. Either way, Apple should replace the phone since this is a hardware issue and a software update is not going to help. There is a one-year warranty on new iPhone 15 Pro Max units so if your phone has burn-in, you can visit the Genius Bar at your nearby Apple Store. You can also call the nearest Apple Store and explain the problem.