Here's why:
* Syllabication: Hyphenation is based on syllables. One-syllable words have only one syllable, so there's no place to divide them.
* Clarity: Dividing a one-syllable word would create confusion and make the text harder to read.
Example:
Instead of "b-reak", it's always "break".
Exceptions:
There are a few rare exceptions, but they are typically used for stylistic reasons or in specific contexts:
* Poetic license: Poets sometimes divide one-syllable words for metrical or rhythmic effect.
* Visual emphasis: In some cases, a hyphen might be used to emphasize a particular part of a word, even if it's a one-syllable word.
In general, it's best to avoid dividing one-syllable words.