Grievous wounds

Why don't people buy them? With tiny thorn mail and calling both being under 1000 gold there is no excuse. A mundo who went like 14/6 just ruined my latest ranked game and no one bought a Grievous wounds item but me ultimate the end of the match when Kayn finally did. By then it was to late of course but what ever. My friends ask me why I don't play ranked even though I have a 60% win rate and play at least at a silver level. Well it's just to depressing. People just don't listen. They won't spend 800 gold for the item that would win us the match because they need that dusk blade.