Swearing Is An Expression of Emotion and Should Be Used Sparingly
Swearing is an expression of great emotion and should be used sparingly, with the notable exception of some works of screenplay such as television shows or animated works.
In my eyes, swearing is an expression of a fair deal of emotion as swear words are often cast as taboo and unacceptable in common discussion. Proper utilization of swear words calls for intriguing analysis of characters who are expressing their feelings, whether angry or sorrowful. If used as but another figure of speech, as littered as metaphors or idioms, swear words lose any impact they could have had; if a character who never swears lets a word slip in a time of weakness, you will think "Oh, this is a real time of weakness."
Because of my own personal beliefs and views, I tend to hold back on swearing in my writing, but if appropriate, a word can slip. Additionally, if a character's arc is to be redeemed from a lower portion of life, transitioning from sailorhood swearing to awesome abstinence would be a commendable metaphor for their transformation. Nonetheless, I hold back on swear words in my own writing.