Poor designs resulting from incompetence. This covers unintentional artifacts. (Intentionally malicious/anomalious designs belong in c/assholedesign)
Nothing's new sub-brand, is supposed to read "CMF"
Bicycle front derailleur that can't be vertically adjusted (Shimano fd-m410-e)
These are used as OEM parts on bicycles, so you could buy a complete bicycle and then find that it's forever limited to small cogs. If you remove the derailleur, notches in the bottom bracket become exposed to water.