If you can't hit, your powers are worthless (again, there is an exception, in the form of the 'pacifist cleric', but let's focus on the other possible characters, some 99.9% of the possibilities). Wo TC created a feat, "Weapon Expertise", that grants, just that, a +1 to hit at low levels (more at high levels, but that's besides the point).
This feat, this simple +1 to hit, is so dominatingly powerful that it's considered a 'feat tax', as all characters, even non-optimized ones, MUST take this feat.
Unfortunately, the RAW ('Rules as Written', the only thing an optimizer can use to make judgments) for monster damage is so pathetically low, the healing so jaw-droppingly high, that this isn't much of a consideration.
Similarly, characters primarily, almost exclusively, defeat monsters by dealing hit point damage.
The other two methods, exploiting weak saves and abuse of the Intimidate rules (both since fixed) are too easily exploited to necessitate any lengthy discussion.
The primary way characters do damage is by attacking (go figure.) And this leads to our fundamental philosophy of optimization in 4e: +1 to hit is everything.
Before you can optimize, you must first understand the game.
Thus, the thought processes for optimization depend on the game.
This is a factor with what one sees in 4e, where very little can affect characters-- you usually can't take away their hand weapons in this game, and even the 'rust monster' of 4e doesn't permanently really destroy magic items (rather it dissolves them into magic essence which needs to be reforged back into a magic item.) Primarily, the only thing you can do to a character is hit point damage and applying temporary inhibitors such as slows, dazes, and stuns, so an optimal character might be concerned about having hit points.