Here's why:
* "Luck" is a noun, and suffixes are usually added to verbs, adjectives, or nouns to create different word forms.
* "Luck" is a fairly self-contained concept. While you can describe "good luck" or "bad luck," adding a suffix wouldn't typically change the meaning in a useful way.
However, there are some ways to express the idea of luck using suffixes:
* -y: This suffix can be added to some nouns to create adjectives. While not specific to luck, it can be used to create words like "lucky" or "unlucky."
* -ful: This suffix can be used to describe something that is full of something. While not directly related to luck, you could say something is "fortune-ful" to imply good luck.
Ultimately, the best way to express the concept of luck depends on the specific context and what you want to emphasize.