I don't particularly care about optimizing "TO THE MAX!" at this point since I'm mainly concerned with learning the general way of the game, so this is basically a question of curiosity, but why would Fighter be any worse then the other classes?
Nor was I suggesting you do so, merely making a statement/answering a question. Now allow me to explain.
Fighters are at their best at low levels. They can take the hits, protect the squishy casters and still do something worthwhile. But eventually (for some, around 5-6th or so, maybe higher for others), the enemies start being able to avoid the Fighter... Or the Wizard starts using spells capable of instantly killing/neutralizing enemies, or do something to stop the foe, but it also stops the Fighter. Now, really, this is true of all melee classes.
But what sets the Fighter apart is his total lack of class features. Barbarians get Rage and it improves with levels, Uncanny Dodge, DR/-, and a bunch of other stuff; Paladins can smite and get a horse, plus the save booster and a little healing, and a handful of spells (which gets a lot better if Spell Compendium and Complete Champion are allowed); Ranger gets a handful of feats for free, due to Combat Style, gets a bonus on damage against some creature and gets a handful of spells (again, better if more books are allowed). (By the way, not including Monk in the comparison because Monks are... let's just say they're not worth the time.
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What does the Fighter get? A lot of feats... Okay, cool? But thing is, the best Fighter feats don't really stack up against the stuff the other classes are getting, and the "best" feats come at a high level, by which time the other classes have effectively left the Fighter in the dust.
(BTW, Fighter 4 nets you Weapon Spec. and two other bonus feats. That's generally seen as the best point to break off, since +2 damage for a reasonably-early feat isn't too shabby.)
There are a number of ways a Fighter can work to keep up, but they require extra books. Generally, the best way to have a good warrior-type for higher-level play is to make an archer. Archery still relies on Full Attack, but you don't have to chase/charge the foe, can still hit flying enemies and have an easier time running away.
Then you look at Wizards, Clerics and Druids... They can do all the tricks all the other classes can, and keep going (at high levels). Clerics can cast Detect Traps and possibly do better than the Rogue. Or Divine Power and make fun of the Fighter/Barbarian/whatever. Druid ties up the battlefield, lets his animal companion (oftentimes at least equal to a warrior-type) run wild and then turns into a bear, just for kicks, then summons a half-dozen pre-buffed animals. Wizard rewrites the laws of reality whenever he feels like it, or instantly kills a foe, etc.
You might say these spells are limited each day, but the Wizard casts Rope Trick and everyone is safe for another 8 hours while they rest and prep new spells. There are ways to force a party out of this trick/system/cycle, but it can be troublesome.
I hope this little explanation helped. I used to spend a significant amount of time at the old WotC Character Optimization forum (before stupid WotC broke their forums), so I've got some pretty serious CharOp knowledge/understanding.
But where I differ is my preference of fun over power. For one thing, I stand by the credo of "A good optimizer builds to party power level," something not everyone understands. Too many folks just want to be the most powerful in the party. Don't get me wrong, I like to play a powerful character, but I don't do it to show up other folks or "be the best."
There's some kind of system out there that determines which classes are the most powerful at givin levels.
Less of a system, more observation and comparison. Look at 20th-level Wizard and 20th-level Fighter. Fighter is essentially one of two things. He's either a Jack-of-All-Weapons or a Specialist (which is also usually a One Trick Pony). He can't fly (unless he grabbed UMD ranks or bought special boots), relies on an enhanced weapon... Wizard can spam Wail of the Banshee 4/day, plus bonus spells. Or Wish. Or Gate.
Let's knock the level down to 10th. Fighter is still either the Jack or the Specialist. Wizard can still auto-kill whatever he feels like, just a little less times/day (3 Phantasmal Killers/day, plus bonus spells).
I don't mean to harp on their thing, if they think it's fun to "crunch" like crazy then go for it and all that, but it sounds like it's kind of missing the point in a way.
Different people enjoy different things. And it really depends on the group dynamic.
BTW, please don't make the mistake of thinking optimizers/powergamers can't or don't RP.
