Why are Pawn Structures so important in Endgames?

Really don't understand why pawn structures are so important. In addition, why is it considered bad to have doubled/isolated/backward pawns?

It’s because pawns defend each other. If you have doubled pawns, both pawns aren’t defended. Doubled pawns are also an easy target for rooks, and many endgames include rooks. Isolated pawns aren’t defended by other pawns, and are also an easy target. Backward pawns aren’t defended and if the backward pawn gets attacked the other pawns won’t have defense anymore. If you have a good pawn structure, the pans are better defended and a king can’t attack the pawns in a paw chain because he’ll have to go to the last pawn first, and then the first pawns can go forward and promote. Pawn structures aren’t only important in endgames, but also very important in the beginning and after castling your king.

Look at this two positions. Which is better for black?

Hard to tell, I'm unfortunately not good at endgames

Actually, i just realised that both of them is a draw…. XD

In both positions the material equal, but still, the second position is better for black.

In the first position, the evaluation bar says +2,8 for white. In the second position, the evaluation bar says +1,6 for black. However, the material is equal and both the kings and the rooks are on the same place. Now you understand?

• Doubled pawns not only don't protect each other, but they can also block your own pieces and make for easy targets that can prove exhausting to defend.
• Isolated pawns must be protected by pieces, which can potentially lead to overloading. This also makes them easy targets, especially later on.
• While a backward pawn might not always be vulnerable, the point is that it's stuck because moving it allows it to be captured freely; moreover, it also must be protected by pieces, which can still be a problem. It can also allow the opponent to take an outpost in front of it if an enemy pawn is near it.

In an endgame, this is all a big deal because both players are trying to push their pawns through and promote. This leads to the following complications:

• Pawns that are doubled can be collectively blocked by just one piece, or even an enemy pawn on the same file, standing in the way. This effectively makes them useless unless the blocker can be removed.
• Pawns that are isolated or backward can be a double-edged sword.
  • One one hand, they are difficult to defend when virtually nothing is left on the board, especially if the side they're on has no rook(s) available to stand behind them. Unless the king can come to the rescue, they're most likely goners.
  • On the other hand, if they're passed, and there's a rook to support them from behind, they can be almost impossible to stop. They can also serve as a distraction.

This was definitely the best answer I've received. Thank you so much