My best friend is the one who brings out the best in me. Henry Ford (early auto manufacturer)

Some friends are really exciting to be with, enjoying sports, entertainment, or just having fun. But hanging around people who cater to your every whim and participate in questionable activities will very likely not improve your character. The best kind of friend is the one who challenges you to be and do your very best, always spurring you on to better things.

An honest answer is like a kiss of friendship. . . .  Wounds from a sincere friend are better than many kisses from an enemy. (Proverbs 24:6; 27:6)