I think a compliment ought to always precede a complaint, where one is possible, because it softens resentment and insures for the complaint a courteous and gentle reception.
Source: In The Ultimate Success Quotations Library, 1997.
-- Mark Twain, (Nov 30 1835-1910), US novelist, journalist, river pilot; The Great American humorist was also known as The People's Author and creator of Tom Sawyer and Huck Finn.