Preparing a blockade on e4.

Obviously 1...Rxf5 just helps White to accomplish his plan by 2.Ne4.

Winning the battle for the e4-square.

3...gxf3 4.Rxf3 Bf4 5.Be3 , with ideas like Rg1+, White obtains a strong initiative.

Clearing the d1-h5 diagonal for the queen with excellent attacking prospects.

Preparing ...Nc6-e7-d5 with a blockade.

Setting the pawn majority into motion.

Black has a clear initiative.

Sacrificing a pawn to install a blockade on e4 with the knight, which will enhance a future attack.