Cargo cult programming is a style of computer programming characterized by the ritual inclusion of code or program structures that serve no real purpose.

— Wikipedia

Most engineers go through a progression of understanding the balance of simplicity versus other values. Oftentimes, simplicity should win.

Examples

Why write a switch statement here instead of employing the strategy pattern?

More generally:

How about using XYZ Gang of Four pattern here instead?

I'm not against these patterns because I'm unfamiliar with them. Quite the opposite. Healthy experience with these patterns should tend to reduce the urge to reach for them.