Using “want” is always direct and sometimes impolite (rude). You won’t (or shouldn’t) hear “want” in retail. For example, “Would you like cream in your coffee?” rather than “Do you want cream?”

When using want in the negative, for example “I don’t want cream”, you can usually just say, “no thanks.”  But, in the situation, “I said I didn’t want cream.” (= very strong and almost angry) use alternative language to avoid want: “I’m sorry, but I’d like my coffee without cream.”

If you are angry and frustrated and need to be direct than use want: “I said three times already I want black coffee, no cream!!”

Make it a habit and drop want from your vocabulary and replace it with would like to avoid sounding direct, aggressive, rude or angry.