I see, I was looking at it wrong. In the way I stated it, it basically says look at all these patterns (in $Date) and report what matches. So it looks at the first character, compares it to all the regexes in $Date, nothing matches, next looks at the first and second characters, compares the regexes in $Date and finds nothing matches. Does the same for characters 1-3 and once it checks characters 1-4 it finds that one of the regexes in $Date does match and it quits.
I was looking at it in the wrong way. Thanks for clearing that up.