Why is the Open Sicilian even played?

The open Sicilian breaks a lot of important opening principles, like wasting a tempo by allowing black to do smth after Nxd4, opening the centre before castling, trading a center pawn for a side center pawn, delaying castling, like what is this? is this a strategic opening trap?

"... Two-thirds of this book deals with 'Open Sicilian' positions, in which White plays 2 Nf3 followed by 3 d4. This is by far the most common way for White to meet the Sicilian. White opens more lines for his pieces and attempts to exploit the fact that he will be ahead in development. Let's take a look at the possible opening moves [1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4] ... White is up in development and can move his pieces more freely. Black, however, has a structural advantage of an extra central pawn, which gives him long-term chances of taking control of the centre. A typical imbalance has arisen. The onus is on White to exploit his lead in development in order to secure an early initiative. If White plays passively or his initiative runs out of steam, then typically it's Black, with the better pawn structure, who enjoys the long-term chances. Thus it's quite rare for a state of 'dull equality' to arise. Often in the Sicilian, if Black 'equalizes', he is already slightly better! This structural advantage is seen in most Open Sicilian lines: for example, the Dragon, the Najdorf, the Scheveningen and the Classical Variations. The major exception to this rule is the Sveshnikov Variation, in which Black accepts pawn weaknesses in return for activity. ..." - GM John Emms (2009) in Starting Out: The Sicilian, 2nd Edition

I still don't understand why you wouldn't go bishop b5+ followed by castling then d4, opening up the center AFTER you have castled

Some books do suggest 1 e4 c5 2 Nf3 d6 3 Bb5+. www.newinchess.com/media/wysiwyg/product_pdf/9068.pdf

@kindaspongey said in #4:
> Some books do suggest 1 e4 c5 2 Nf3 d6 3 Bb5+. www.newinchess.com/media/wysiwyg/product_pdf/9068.pdf

I know, but why do grandmasters, titled players, experts, who suggest following opening principles, most of them, play the opening principles, which doesn't make sense on so many levels? It just seems like a no-brainer to develop the bishop and more importantly, the pawn structure! why do you allow black to enjoy a nice position with TWO central pawns? It now looks like a suicidal move to me, and there is no 'initiative'. If white was offered initiative, then no one would be playing the siclian.

Because d4 fights for the center, opens the DSB and after the exchange, white has a centralized knight and black has not developed a piece and the DSB is still blocked in, so black is down two development tempi (+whites knight is in the center).
In return it is black to move and black has a central majority.

That is why the open Sicilian is so popular, it provides both colors with winning changes due to the imbalances.

Edit: Also white has a huge initiative in the Sicilian, just look at high level games.

Still, I don't agree that white has initiative.(Initiative, as far as I'm concerned would give an advantage, or the ability to dictate the middlegame or opening by making threats). against d6, why don't you go bishop b5+ followed by 0-0 and THEN d4? or even c3 followed by d4 vs 2.e6? Fine, black is down 2 tempi, but you have moved a developed piece twice, which breaks ANOTHER opening principle. so why?

White didnt break any principle by moving the knight twice, because black took on d4, which also costs a tempo. Yes Bb5 and c3 are valid alternatives, but that doesnt make the open Sicilian any worse.
You should really study some high level games in those variations, before you judge them as inferior, especially at your playing level.

@KarlDerKaese said in #8:
> White didnt break any principle by moving the knight twice, because black took on d4, which also costs a tempo. Yes Bb5 and c3 are valid alternatives, but that doesnt make the open Sicilian any worse.
> You should really study some high level games in those variations, before you judge them as inferior, especially at your playing level.

Right. To my understanding: White's knight went from g1 to d4. black's pawn went from c7 to ??? Each one cost 2 moves. but at the end of the sequence, it is black to move. I think black has gained a tempo here. If white had played Nc3, he would have 2 pieces to 0 pieces. if white played d4 and took, white would have a 1-0 piece developed, and so on. if it takes 1 tempo to develop the dsb for white, then so it be for black. Feel free to criticise me (this just doesn't include the modern variation btw

It takes white 3 moves to get the knight to d4 (d4, Nf3, Nxd4) and black two moves (c5, cxd4). After this exchange white has developed a knight (+1), moved it to d4 and opened the dsb (+1). So white spends one more tempo in this exchange but gains two development tempi + the knight moved to d4.