As many as it needs sounds so practical.
I have a rule that it has to be revised -- cold, which is to say more than a week after I last worked on it -- after any pass has produced major changes. Like a scene which shifted POV.
But what if you've gone through a pass and produced no major changes? It could be just that you are cranky, which does have a certain impact on your judgment. Being elated and thinking it the best thing since sliced bread might be just as problematic, though it's not a problem I've personally had much to do with.
Then, that crankiness could just be an unwillingness to print it out and get it out in the real world to face the slings and arrows of outrageous fortune. Or sheer sloth.
It's hard to judge sometimes.