More downloads/users than purchases?

So we've got one app live on AndroidPIT right now, and have noticed that we have more downloads/users than purchases. Can anyone explain to me how this is possible?

Tobias, I think Vorpal means why his figures do not match.

@Vorpal: For instance, the download figure increases when someone downloads an update. Or if someone re-install the app on another device. Thus, you sales and downloads may not match.

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Right - you have more downloads then purchases, because

- one User (purchase) might need more then on attempt to complete the download (starts i.e. two times)

- or the user purchases the app and downloads an update afterwards

So, this you user makes one purchase but possibly more than one download. But, it is still the same user on the same device.

I see, that makes sense. Thanks for your help