Thought Experiment: Your character has smelly feet. What image sprung to mind?
What was their gender?
What was their age?
What kind of personal hygiene did you assume?
Even one small detail can affect characterization. As part of the ‘show, don’t tell’ goal of good writing, you shouldn’t neglect the opportunity to give insights into a character by tapping into the five senses. A woman with calluses on her hands could be a farmer or a sword-mistress. A man with silky soft skin is unlikely to work in harsh environments. A child using a loud voice may be excited, or live with a deaf relative. Using this technique, you can hint at their personality or identity without having to ‘spell it out’.
You can get stinky feet by walking in Wellington boots all day, even if your hygiene is excellent. But if your character has just taken off their shoes and you need to evacuate the house, they may have a medical problem. Depending on how likeable you want that character to be, I suggest that explain why their shoes stink so badly. In my Steampunk narrative, it isn’t the feet that stink, but the boots, as they are slowly dissolved by the chemicals used in the laboratory.