OP:
I almost always follow your rule #3, that BTW almost always satisfies rule #4 too. Rule #5 not an issue for me, my backlog is huge due to lack of time, but sooner or later I want to play all my games. I don't follow rule #2 because, as I prefer physical format, if I find a game I'm interested in at some shop at an attractive price, I get it, as delaying the purchase and possibly not finding it anymore, could cost me more time and money, either having to order it and pay for shipping, or ordering it at a shop and not obtaining anymore a time-limited discount. I tend to buy few games anyway.
I'm currently a PC gamer, but I'll most probably follow rule #1 if and when I'll buy a console again (my last one was an Intellivision).







