If dust, lint, or other debris from your trouser pocket gets into the USB-C port of your iPhone, this is generally a user-specific maintenance issue rather than a generic iPhone problem. Many people routinely carry their iPhones in pockets, and over time, fabric lint, dust, and other small particles can naturally accumulate around or inside the charging port.
The USB-C port is an exposed opening, so it cannot be completely protected from environmental debris during normal use. How quickly debris accumulates depends on factors such as where and how the iPhone is carried, the type of clothing, the environment, and how frequently the port is exposed to dust or lint.
Therefore, if you notice charging difficulties or the USB-C cable does not seat properly, it is worth checking the port for visible debris. Keeping the charging port clean is part of normal device care and maintenance. However, avoid inserting sharp objects or forcing anything into the port, as this can damage the contacts. If the port appears damaged or the problem persists after removing obvious debris safely, Apple Support or an authorised service provider can inspect it.