I'm not impressed with the Swipe methods of app closing, it's imprecise at best and very cumbersome. Just enable the "X" on Swipe from top... like with the mouse... bang, bang done.
Swipe drag, hold, wait... its a bunch of horse hockey. Simplicity folks. Make it as simple as possible, that was the advice of someone very smart, we should never forget that.
I don't know what MS intended when they put in the swipe down gesture to close the app rather than a simple "X", but let me share you my opinion on this matter.
As an app developer, I understand that I get blamed for everything, including things that are out of my control. My current main app that I give all my support to is an office alternative app called Modern Word. When I first published it, I included a feature for the user to be able to delete document files. After all, this is a self-contained app, and people would expect that, yes?
After just a couple weeks, the hate mails started rolling in. People were accidentally deleting files they didn't intend to using my app, despite the popup that says "you are about to permanently delete this file. Are you sure?" with a choice of "yes I'm sure" and "No, cancel".
And let me tell you, these hate mails were nasty. One guy said he worked for 5 hours on a paper and he accidentally selected it to be deleted with my app. So, it was my fault.
So, I took this option out. Then the hate mails started rolling in about this option being taken out.
Here's another example. My app would close just like every other metro app: swipe from top to bottom. Well, I started getting hate mails from people who accidentally close the app before they saved the file or while they were working. Again, people swiped from top to bottom of their devices and they blamed me for their action.
To solve this, I wrote a script that prevents my app from closing even after people close it. So, you can close my app, come back tomorrow, open it, and everything appears as if you never closed it. That shut people up.
The point is while MS never released any data, I suspect that they got many many many many hate mails from users who accidentally clicked on the "X" and closed down whatever they were working on. Heck, my app used to close after people swiped it down from top to bottom and I still got hate mails from people who "accidentally" swiped down from top to bottom.
Part of being a developer/programmer is we have to consider scenarios where people screw up. Why? Because we always get the blame.
