How Do You Spot Weak or Undefended Pieces?

Are u using techniques or solving many puzzles maybe?

Perhaps the best place to look for weak-or-undefended-piece problems would be in the record of one’s games. Some portion of the mistake identifications may consist of weak-or-undefended-piece examples. Here is an example that was discussed at https://lichess.org/forum/general-chess-discussion/how-do-i-avoid-multi-move-blunders :
At [Site "https://lichess.org/TIr3rjIB"], one might look at the situation after 1 e4 e5 2 Nf3 Nc6 3 d4 Nxd4 4 Nxe5 g5 and notice the ~4.3 --> ~1.0 transition associated with the imanoob424 choice of 5 c3. It turns out that the explanation is the undefended nature of the d4-knight.
For a player, I would think that weak-or-undefended-piece examples would continue to turn up in the game records about as long as the weak-or-undefended-piece thing continues to be a problem. For more complicated examples, I would think that one could turn to a book like Winning Chess (Batsford edition by Chernev and Reinfeld).
https://web.archive.org/web/20140708093415/https://www.chesscafe.com/text/review919.pdf

weak piece is not defended or is attacked as many times it is defended. Obviously need access to that piece as well.

CM ChesswithAkeem suggests checking what did the piece that was moved last do? If it guarded another piece, you check of that other piece is now unprotected.

@Bishop1964 said in #4:

@kindaspongey ... Are you some kind of Lichess artificial intelligence ? ...

The CLOUDFLARE thing seems to believe in me.
"... Did we not contain conscious brains ourselves, how would we know that other brains are conscious? Truth be told, you can really only know that you are conscious, and it seems polite to give other people the benefit of the doubt. ..." - CGP Grey
https[colon]//www[period]youtube[period]com/watch?v=nQHBAdShgYI

Look around the board with your eyes, spot a piece, take it.

https://chessmadra.com/vision

@alijeba said ^

https://chessmadra.com/vision

I think that training aid would be better if it didn't tell you how many pieces were hanging, undefended etc. In an actual game you don't get an indicator telling you there are so many hanging pieces etc!

Do tactics training.