Not all analogies will make perfect sense in all situations, analogies are used to put the situation into a more commonly known and could be understood easier. Its much easier to say something is bigger when you have something to compare it to. Or Costs more, or has this over that, or advantages vs disadvantages.
MArathon: if the guy at the start isnt doing well, what proof will make it so he has the stamina to finish? Its very possible he just drops out or completely makes an underdog win, either way, the analogy here is to show that, a slow start up has more disadvantages then a full flat out burst. Every racing game has some sort of bonus boost to speed that you get if you press the accelerate button at the right time when the race starts so that you can get that bonus speed boost. Coincidence? No, because it is more advantageous to have that boost rather then hoping your stamina carries you, because what if the opponent has the stamina to keep his speed? and his speed is faster then you?
Cars: Expensive cars we want for luxury, regular common average cars we want for purpose. While it is hard to relate this to consoles as not everyone needs a console. However there are still people out there who cant live if they dont get a PS3 or a Wii or whatever. However the analogy here is to relate sales to price. Higher Price, generally no matter what product it is, sell less than a cheaper alternative. General economics say theres an equilibrium where if the market left untouched, there will be a buyer for all items or all prices of both the high end product will drop to a lower price and the cheaper item will increase to that same price and equaling out. While rarely happens in real world economics, this is what is supposed to happen. Possible PS3 price cut? maybe, possible upgrades to wii means increased prices so it is the same situation. It is trying to find equilibrium.
Now then back to the topic, PS3 cuts will probably not happen, and sales arnt going to see a magically increase in numbers. the selling rate of a product usually stays the same with little fluctuation in the market unless outside forces persuade otherwise. These forces people keep saying will happen are the christmas sales that will supposedly boost the pS3 sales to make a come back, however everyone knows, ps3 is expensive and wii is cheaper. There is much more exposure for Wii than PS3 and how do you know that the xmas sales wont boost Wii and Xbox numbers so it still looks like the PS3 is trailing? That is my arguement, take or leave it :P
your cars anologies is a little silly.....ferraris are not being sold to everyone. you ands I know that for PS3 to be relevant in this generation they have to move more units and if they want to keep selling like ferraris while nintendo keeps selling like civics more power to them