If you had broken some important rules, your account would have been banned or something, not just a plummet in browse ranking.
There is a limbo in between, where your stuff is ok, but they delist you anyways. I have seen such an account that would fall under those quality guidelines. But if you are not listed, you do not appear in browse at all.
The old post leafo linked says it clearly, the browse popular algorithm has some parts of real popularity and some parts of boosting for new things mixed in. So erratic behaviour is to be expected.
But if you really were bumped back to last place for some popular tag with thousands of competing games, that does sound like a side effect. Maybe your game looked unavailable due to an update while the index of browse was reshuffled or something silly. Or they lost access data due to their changing servers in the background. There is a thread about that somewhere, that they are migrating some services.
Otherwise there really do be strange numbers. Look at popular games for tag fps. View last day and last week. The first has only 3 games in it. The other 26. Your game is not in there. It is again in the 30 days and overall. Since your game is only 10 days old, it seems strange, that it does not appear in the 7 day category. But, there are a gazillion tags and the popular sort is strange and with small numbers, odd results can happen very easily.