The cpu's (all levels) are nothing more than cold, lifeless, programmed machines that are designed to react to
all situations in the
same way
all the time.
I'm going to use a Melee example. (I don't have a Wii and I just came back from fighting a level 9 Ganondorf with Fox... Yes, I know I'm a hypocrite for training on level 9 cpu's but i'm bored...And, all my friends ever want to play is Brawl.

)
Anyway, here's some examples of some bad habits that I've developed from playing against level 9 Ganondorf and why I'd probably lose to an experienced Ganondorf user:
-Whenever I've successfully launched Ganondorf high into the air, I never follow him up there. (Because, I know I'll just end up getting a d-air shoved down my throat)
So I wait for him to DI back to me. (
Every level 9 will try to DI back to you no matter what.) And, if he's directly above me, Ganondorf will
always go for a d-air.
I know this. So then all I do is run away and SHFFL him until he comes back.
-If Ganondorf (or any Level 9) is in the air and I shoot them with a laser, they
always aerial dodge, leaving me a chance to hit them with anything. (N-air, b-air, up smash, etc.) This works the first time, the second time, the eightieth time, etc., etc... They never fix their mistakes.
-If at any time, I am above Ganondorf, he will hore out his up-B in an attempt to tack on damage. Sometimes, he just throws them in randomly while I'm waiting for him to get at me and then I rush over there and charge an up smash while he's trying to land.
-If I miss a tech and i just lay there waiting to see what he's going to do, he will walk slowly to me and at a certain point he will start doing down smashes over and over again trying to get me to roll into them.
-If any level 9 is standing on the ground across the field from me and I laser them, they will almost always
perfectly power shield it right back at me.
Needless to say, I try not to shoot too many lasers while they're on the ground.
Cpu's do not adapt. The ability to defeat level 9 cpu's consistently just means that you've succeeded in memorizing their attack patterns and programmed reactions.
You don't realize it, but when you're training against a cpu that does the same thing over and over again, it's only teaching YOU to do the same things over and over again.
If I were to face an experienced Ganondorf user tomorrow, I'd have a hard time ignoring my instincts during battle. (unconsciously thinking lasering him while he's in the air will result in his character doing an aerial dodge, expecting an up B at close proximities, choosing not to laser him from afar while he's on the ground)
tl;dr version:
Bad habits are bad.
