Answers.Body: <p>A blunder is a game-changing move. Nb8 does not change the result of the game which is utterly and completely lost regardless of black's move. Earlier in the game black <em>did</em> blunder when it gave away its queen.</p>
  <p>The reason for the &quot;!&quot; part of the &quot;?!&quot; (dubious move) notation in this case is because moving the knight opens up the line of sight of the d7 bishop.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-02-20T10:47:20.593Z
Answers.LastActivityDate: 2021-02-20T10:47:20.593Z
Answers.UserDisplayName: Brian Towers
Answers.Body: <p>Computer annotations these days commonly use <code>?!</code> to indicate moves which are noticeably worse than the best move, but not bad enough to warrant a <code>?</code> or <code>??</code>. There's not necessarily any merit to the move, as there would have been in the old meaning to the annotation.</p>
  <p>The program I use to auto-annotate my games uses a threshold of 3 for <code>??</code>, 1.5 for <code>?</code>, and 0.5 for <code>?!</code>. Other programs may use other thresholds, but the idea is the same.</p>
  <p>The program I use will not use these annotations for the losing side once they're already losing by a sufficient amount. Apparently lichess will still use <code>?!</code> but not <code>?</code> or <code>??</code> annotations, in this situation. I believe this makes some sense, as the &quot;best&quot; move in a hopeless situation is not necessarily the move which postpones the mate for the longest. But the computer isn't that great at finding &quot;merit&quot; in objectively losing moves.</p>
  <p>Can there be merit in a move that allows a forced mate? There wasn't in your case, but it can happen. I remember one game from my high school days where I was hopelessly losing (down a piece, and my opponent was about to promote) but I noticed I had a draw possibility if I could get my queen to a certain square. The catch was, it would take two moves to get there, and my opponent had a forced mate in 2 once I made the first queen move. I went for it anyway, he didn't notice the mate <em>or</em> my draw threat, and I stole a draw. Playing the &quot;best&quot; moves at that point would have been a certain loss.</p>
  <p>I'm not quite sure why I still have the notation sheet for that game, but I do, so here's how that one ended:</p>
  <pre><code>[FEN &quot;1Q6/1Npqkp1p/2p5/P3p3/2P1p3/1P5P/5PPK/8 w - - 0 36&quot;] 
  
  1.a6 Qf5?! 2.Qxc7+?? (2.Qd8+ Ke6 3.Nc5#) Kf8 3.a7?? Qf4+ 1/2-1/2
  </code></pre>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-02-22T05:39:08.757Z
Answers.LastActivityDate: 2021-02-22T05:39:08.757Z
Answers.UserDisplayName: D M
Body: <p>In a recent game against a weak computer opponent on lichess, I (white) was in the following position:</p>
  <pre><code>[FEN &quot;Q4k1r/p1Nbbppp/1pn1p3/8/5B2/5N2/P1K1nPPP/R6R b - - 0 1&quot;]
  </code></pre>
  <p>The AI played the move Nb8 giving white a forced mate in 3, annotated by the lichess analysis board as a Nb8?! -- it looks like Bd8 is a better move by blocking the check with a supported bishop.</p>
  <p>However, at least to my novice understanding, a move into a forced checkmate (let alone a relatively easy-to-see one in three moves) instead of a far better alternative should be a blunder, not a dubious move (which I understand as &quot;questionable but possibly having merits&quot;). Is there something I'm missing about the nature of this checkmate which makes Nb8 dubious but &quot;possibly having merits&quot;, or is it a case of wrong automated annotation?</p>
  
Tags: <blunder><annotation>
Title: Why is this move into a simple forced mate annotated dubious and not a blunder?
ThreadText: # Why is this move into a simple forced mate annotated dubious and not a blunder?
  
  (Asked by: username_0 on 2021-02-20)
  
  In a recent game against a weak computer opponent on lichess, I (white) was in the following position:
  [FEN "Q4k1r/p1Nbbppp/1pn1p3/8/5B2/5N2/P1K1nPPP/R6R b - - 0 1"]
  
  The AI played the move Nb8 giving white a forced mate in 3, annotated by the lichess analysis board as a Nb8?! -- it looks like Bd8 is a better move by blocking the check with a supported bishop.
  However, at least to my novice understanding, a move into a forced checkmate (let alone a relatively easy-to-see one in three moves) instead of a far better alternative should be a blunder, not a dubious move (which I understand as "questionable but possibly having merits"). Is there something I'm missing about the nature of this checkmate which makes Nb8 dubious but "possibly having merits", or is it a case of wrong automated annotation?
  
  **Tags:** blunder, annotation
  
  
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  ## 2 answers
  
  ### Answer by username_1 on 2021-02-20. Score: 6 | Accepted answer
  
  A blunder is a game-changing move. Nb8 does not change the result of the game which is utterly and completely lost regardless of black's move. Earlier in the game black *did* blunder when it gave away its queen.
  
  The reason for the "!" part of the "?!" (dubious move) notation in this case is because moving the knight opens up the line of sight of the d7 bishop.
  
  
  ---
  
  ### Answer by username_2 on 2021-02-22. Score: 5
  
  Computer annotations these days commonly use ?! to indicate moves which are noticeably worse than the best move, but not bad enough to warrant a ? or ??. There's not necessarily any merit to the move, as there would have been in the old meaning to the annotation.
  The program I use to auto-annotate my games uses a threshold of 3 for ??, 1.5 for ?, and 0.5 for ?!. Other programs may use other thresholds, but the idea is the same.
  The program I use will not use these annotations for the losing side once they're already losing by a sufficient amount. Apparently lichess will still use ?! but not ? or ?? annotations, in this situation. I believe this makes some sense, as the "best" move in a hopeless situation is not necessarily the move which postpones the mate for the longest. But the computer isn't that great at finding "merit" in objectively losing moves.
  Can there be merit in a move that allows a forced mate? There wasn't in your case, but it can happen. I remember one game from my high school days where I was hopelessly losing (down a piece, and my opponent was about to promote) but I noticed I had a draw possibility if I could get my queen to a certain square. The catch was, it would take two moves to get there, and my opponent had a forced mate in 2 once I made the first queen move. I went for it anyway, he didn't notice the mate or my draw threat, and I stole a draw. Playing the "best" moves at that point would have been a certain loss.
  I'm not quite sure why I still have the notation sheet for that game, but I do, so here's how that one ended:
  [FEN "1Q6/1Npqkp1p/2p5/P3p3/2P1p3/1P5P/5PPK/8 w - - 0 36"] 
  
  1.a6 Qf5?! 2.Qxc7+?? (2.Qd8+ Ke6 3.Nc5#) Kf8 3.a7?? Qf4+ 1/2-1/2
  
  
  ---
  
  