NUMA will not allow more then two of your maps on the newest page at once, so by posting all four of your maps together these last two which are fairly decent will not be on the newest page (where most people check for maps) for a long time to get maximum attention. Most advice is to post a maximum of five a day, perhaps one an hour, to keep all your maps on the front page for the longest length of time and it also shows you've spent time on each map.