When you sort something, e.g. either by "Likes" or by "Last Post" or by "Responses", you typically assume that the topics with the highest values are listet on top on the first click. Currently, you get the least interesting results first and have to click yet again on the table header to get the interesting results.
Since most admins don't bother to change this setting, this annoying behavior is present in many boards (even here). Descending order as the default order would be very nice