Did you know April is National Humor Month? While the idea for a month of laughter was conceived to honor the healing power of humor, it doesn't mean everyone who participates is actually funny. In fact, some people are so bad at telling jokes, they actually ruin the moment (or day, if they're really terrible). In honor of the month, we're taking a look at the top 18 reasons why some people's jokes just aren't working. Keep reading to see if you're committing one of these faux pas of funny.