Yea, that's why I said preferably overnight. A lot of people don't want to start preparing their meals a day ahead of time so a few hours won't be horrible but won't be the best it could either. Happy median.
It's the best after 2-3 days in the fridge (this requires less yeast though, for a slower rise). A couple hours really isn't doing much of anything for taste/lactobacilli production especially considering the time it take for the dough to go down to the temp of the refrigerator. The only real reason to put it in for a couple of hours is if you make the dough, but you don't want to use the dough til later that day. If that's the case you could always just put a little less yeast into the dough so it rises slower, and leave it at room temperature too (covered, of course).
The only reason I bring this up is in case someone's like "I wish I could eat this pizza sooner, but I have to put it in the fridge for a few hours first like it says in the directions".