Pushing a pawn
I am making this post for those lower ranked, as a way to help them learn.
How often do games end up won or lost, because of a single pawn push? More often than people think! And deciding to push a pawn in middle game is probably one of my largest time killers.
Pawns are the only piece that cant move backwards, so a quick gain in position isnt always enough to make it the right move. In a game I am currently playing OTB (I am much past the point posted and am confident I should win now so feel free to comment or to look at the game), I spent almost an hour trying to find a move better than a pawn push that jumped out at me instantly. (Of course one should always spend a few minutes in OTB games analyzing each move) My opponent and I are both ranked about the same (less than 50 points difference) and he decided to play a sicilian - accelerated fianchetto (of which I hate going up against sicilian, but it is a line I have studied a good bit just because of my early problems defending against it) 10 moves in, we both were through the general opening phase, and he is swinging king side. g4 is feeling the pressure of two knights and his unmoved light bishop. Two candidate moves are f3 and h3, though h3 is just begging for the light bishop to sacrifice, so I discounted it.
So f3... f3... it will create a nice pawn chain. Protect g4, but it is permanently moved... less king protection later. (not like anything was currently threatening)
So I made the push of course. But for newer players reading this, a couple of things to keep in mind for your own games: Pawn pushes can strengthen and weaken certain colors on the board. And one thing a stronger player will utilize is your weak squares. Pawn pushes that initally look good, and aggressive, can lead to backwards pawns later, obvious targets of aggression. And finally sacrifices. Moves designed to completely obliterate pawn structures (or at least cause serious problems) are almost always precipitated by moves that happen 3 or more moves before, when pushing a pawn seemed like a good idea. So don't just toss them out there lightly, thinking "its only a pawn" as a king-pawn win only happens if you are the one up a pawn.
Once the game is over, I will post it below to show how this one pawn push led to my opponents ultimate demise. (Rather it led to him trying to rethink how to approach the defense, and he made two critical mistakes back to back)