The Cards Resource

[psychospacecow]

No offence, but this is starting to sound like Dota 2. There's a standard, efficient way to do things, if you don't do it that way you're losing the match for sure. I remember when you could just make a deck with whatever cards you wanted, as long as you have a reasonable amount of Spell/Trap cards and enough Level 4 or lower monsters, you could play a duel and have fun.

Archetypes are needed to fit each monster under a common label, and it used so certain decks cannot exploit the effects of other archetypes. Imagine how broken all the burn decks or deck outs would be if they had the power of defense decks.

Sorry, I'm not understanding this. "Burn decks"? "Deck outs"? "Defense decks"? Can you explain how would my deck suffer or break if I were to have no archetypes?

Sorry, I have a tendency of doing that.
Now, don't get me wrong. You can use a whole lot of different kinds of decks and such, but if you have a lot of cards that don't work well together, like zombies and gravekeepers (fundamentally enemies effect-wise), then its going to end poorly.
Not all decks use archetypes, like Chaos Dragons,
http://yugioh.wikia.com/wiki/Chaos_Dragon
which may employ certain archetype cards but aren't bound by them, but that's some kind of difficult of make work.

A burn deck is a deck designed to do damage to your opponent without attacking.
A Deck out causes your opponent to, well "Deck Out", or run out of cards and lose because they can't draw anymore.

Defense decks usually rely on your opponent bashing into defense position monsters, setting off their effects, or being too scared to do that, and letting you set off their effects. (As these are naturally slower, they've pretty much been phased out over time though there's still a few decent variants)