Revolutionizing pregnancy tests?

Why do all pregnancy test have to have two lines that appears if you are pregnant? When you REALLY want to get pregnant, you see the second line if you stare long enough....even thou it's not there. I was sure I saw a line (2 days before the witch came), because in a certain light, from a certain angle, it could be a line, a really faint one...

NOW, if the pregnancy tests had had TWO lines appearing when you're NOT pregnant, it wouldn't be so easy to misread them. Than the second line would NOT appear if you were pregnant.

Good idea or what?

I think I'm going to revolutionize the world of pregnancy tests;)