does advancing a pawn ( like e4-e5 or d4-d5 ) in the opening bad for us??

does this move [ advancing a pawn to the fifth squares (as for white) in the early stage of the game ( opening ) ]  bad for us??? cause I think ( just my view ) , advancing the pawn in the early stage will make us harder to defend the pawn, and the squares attack by the pawn are pretty hard to be used as an outpost for the knight ( cause its on the 6th rank, pretty hard to reach ). 

Is my thinking wrong...??? any comments??? just feel relax to              leave whatever comments........              

It is good in some positions, and bad in others. There cannot be a generic answer.

Your post is well reasoned and logical. It is in details that your reasoning and logic will be refined to a rigorous system.

There are advantages and disadvantages to every move in chess.

I will explain in detail with my next post.