The Grob Attack... not often seen, and for good reason. It immediately weakens White's Kingside, and shows no intention of occupying the centre (often the most vital area of the chessboard, this is why 1.e4 and 1.d4 are most common)

Black has 3 minor pieces developed compared to White's 1, and has a stronger hold on the centre, and so is better positioned currently.

This is ok, as it's forcing the Bishop to move again, so Black loses some tempo.

Same idea, Black's pieces get pushed around, but soon White will have over-extended pawns, which can create targets for Black.

3 of Black's pieces have been pushed around, but Black is still ahead in piece development.

It was probably better to simply recapture the pawn.

Black allows e4 to fall because instead plans to take h3, meaning the pawn on g5 won't be reinforced

Castles, because King safety is one of the 3 most important elements of the opening (alongside pawn structure and piece development)

Closes the dark-squared bishop diagonal, as well as stops c5 and a5 knight advances

Good move, hitting the h3 Knight twice as well as f7, so White can at least equalise in material