It does seem nicer to ask after, but then again, 99% of us simply close the tab after the download starts. We just do it automatically.
> 99% of us simply close the tab after the download starts.
Really? On most sites that I visit, I 'Save As' every link that I care to download, so that there is no separate tab to close. (But maybe you were referring only to this specific site.) Maybe the solution is just to make sure that there's more of interest on your download page than just the download button?
Not necessarily. It's not like you expect the buyer to do a careful analysis of what it's worth before they pay. You can usually decide this sort of thing based on very quick impressions. Also, there's the aspect of it just seeming nicer to ask after the download has happened. Then it's clear that you already have the product, now it's up to you to decide what to pay for it, if anything at all. Here people have been tricked into thinking they had to pay and begrudge the author.