Comment 5 for bug 1365060

This is a UITK bug, because a software update is just one of many examples where it is not accurate for a progress bar to display a percentage. Another common example is downloading a Web page: the browser hardly ever knows ahead of time the total size of the resources in the page, so it's smoothest if it compensates for probable late discovery of new load tasks by using an accelerating curve, for which a percentage would be meaningless. Another example is syncing an Imap account: a mail client doesn't know how many messages it will need to download, or whether any of them contain huge attachments, until long after the sync has started. Even when a percentage is accurate, it's both redundant and hard to read; but often it isn't even accurate.