The rabbis refined that to only permit new garments – presumably because of the inclination to put a crease in older clothes (harder to do with new ones) which would not be permitted.
All this leads to a discussion on our page about the importance of a scholar to appear in clean clothes in public:
R. Hiyya b. Abba said in R. Johanan's name: It is a disgrace for a scholar to go out with patched shoes into the market place.
Any scholar upon whose garment a [grease] stain is found is worthy of death.
Ok, they didn’t mean literally (can you imagine the courtroom scene? “Your honor, exhibit A – the offending stain!”) They meant that if a scholar wants to be treated with respect, he needs to treat himself with respect.
Even in the clothes he wears.