What Makes a Good Lead Magnet?

What makes a really good lead magnet? I mantot go through a checklist here in a minute, but there are so many different kinds. You want to be giving that information away, something that people could or would buy as typically. So what is it that the lead magnet should do if you are wanting people wants it to be irresistible? And i feel like this particular article did a nice job of summarizing thee seven things that a lead magnet shoulddo.