Why do Flies Zip Up?

Here's something I don't understand. Pants, that have zip flies. You zip them UP, so they can fall DOWN, and cause you embarrassment. Why not just make them so you zip down, so it stays like that? Similar to how you have to attach the zipper on a sweater? Or is there some completely obvious reason they don't do this that I am missing, or is this just common sense?

Good question... I'm guessing the zipper would break a lot easier if it was like that?
:O You could be on to something... Well if you do become famous for inventing a improved zipper, make sure to say that 100 helped you out.

My zipper always falls down. The ones on my zip-up jerseys never break, so why not on pants?
Thanks for the help, you'll be credited. :P

Because pants need to be able to unbutton.... -_-

Its impossible, cause when you zip down, the pants get bigger waist wise, then when you get them on, you zip them up and they fit better.

does that make any sense? don't know if I'm explaining it right.

Why not eliminate the button altogether?
Demyx, doesn't that depend on your waist size though?

Ahm, when you undo your zip (oposite of up :P) you are making the top of your pants/shorts w/e larger, hence easier to get out of... If you zipped down there would be the same size up the top of the pants which would make it pointless to have a zip in the first place... 

"Because pants need to be able to unbutton.... -_-

"

"Ahm, when you undo your zip (oposite of up :P) you are making the top of your pants/shorts w/e larger, hence easier to get out of... If you zipped down there would be the same size up the top of the pants which would make it pointless to have a zip in the first place... "

It works that way for girls, you're not a girl, are you?

"efrucht said:

"Because pants need to be able to unbutton.... -_-

"

I immediately thought of that. I wish but it would be hard/weird to go to the bathroom through the hole in your pants... (No unbuttoning)
"

"Ahm, when you undo your zip (oposite of up :P) you are making the top of your pants/shorts w/e larger, hence easier to get out of... If you zipped down there would be the same size up the top of the pants which would make it pointless to have a zip in the first place... "

"Ahm, when you undo your zip (oposite of up :P) you are making the top of your pants/shorts w/e larger, hence easier to get out of... If you zipped down there would be the same size up the top of the pants which would make it pointless to have a zip in the first place... "

smart...

"Ahm, when you undo your zip (oposite of up :P) you are making the top of your pants/shorts w/e larger, hence easier to get out of... If you zipped down there would be the same size up the top of the pants which would make it pointless to have a zip in the first place... "

Zips Fly High when the chick says bye

Along with the whole pointlessness of the zipper if it zipped down, wouldn't any time your legs stretch out a bit unzip it, anyways?  I mean, you take a zipper and pull the two sides apart, and it'll unzip...

It's not as bad as it falling down all the time though.
I was not thinking clearly before, I think this is still a good idea. There is no need for a button, because you attach the zipper up at the top, like you would a zip-up jacket. Then just pull the zipper down. Where is the flaw?

Because if the zipper joined at the top then when you undo the button you wont be able to pull apart the jean to make it easier to get out of.

I bought these jeans recently with buttons, like 4 of them, no zipper, I wondered what the hell I was meant to do, it's so annoying unbuttoning 4 buttons just to take a slash.

"Because if the zipper joined at the top then when you undo the button you wont be able to pull apart the jean to make it easier to get out of.
"

What do you mean?  How could they zip up?  If you mean like that they attach at the bottom then you'd have a little whole in your pants.

"Black_Raven said:

"Because if the zipper joined at the top then when you undo the button you wont be able to pull apart the jean to make it easier to get out of.
"

But there is no button.
"

Okay, let me explain. There is no button. Instead, you'll find the join up part of a zipper. You join it up, then you zip it down. DONE.
To undo, you zip it up, then un-join the zipper. You may now take of your pants.
I'll try and make a picture tomorrow.

Its not a question of up or down but side < to > side

Now how the hell would that work?

Really, I'd like to see how that would work. I'd buy.

Button, more important than zipper. Confirmed. I can usually pull my pants up and down without unbuttoning or unzipping them. I don't even unzip when I'm taking a leak, I just pull the junk out...

"Okay, let me explain. There is no button. Instead, you'll find the join up part of a zipper. You join it up, then you zip it down. DONE.
To undo, you zip it up, then un-join the zipper. You may now take of your pants.
I'll try and make a picture tomorrow.
"