user10380: Suppose a chess game was decisive but didn't go to checkmate. Why does its notation not say whether the loser resigned or lost on time?
There are plenty of NAG symbols; even some ($136-$139) relating to time pressure. Why not for "White/Black resigns" or "White/Black lost on time"?
If we don't know because the only information known is what's on the scoresheets, then that doesn't answer the question; it merely redirects its focus: Considering that this fact is needed so that people know, and can say, how the game ended, why hasn't FIDE made it a law that players should record this on their scoresheets?
I know that players are not obliged to record this. I'm asking why it has not been thought necessary to oblige players to do this.
I know that PGN has a Termination tag, whose value is a string which someone might use to explain how come the game ended. But a game's score can be stated in a context which is not PGN. Even in a PGN file, the tags pertaining to a game are not part of its score (what PGN calls its "movetext"). Even among PGN tags, Termination is optional.

user32606: An answer to your question needs to go back to the beginning of PGN, which was invented by Steven Edwards in conjunction with countless contributors. Let's quote the man:

...it is important that future revisions to PGN must include a public discussion period. In fact, those of you who were reading the chess newsgroups back in the 1992-1994 time frame will recall the many polls and extensive discussion articles. I personally received uncounted hundreds, perhaps thousands of e-mails on the chess standards topics...

This teamwork under Stevens lead happened on rec.games.chess (to be found here). Todays kids can think of a discord server.
It is unlikely someone is going through all of it, and sadly, Edwards has passed away.
Most likely, they couldn't see a need for this since you really only miss the distinction between flagging and resigning, and what's the point of knowing when there is no move time indication anyway.
Another hint could be given by the paper scoresheets they had at their hands; if these didn't feature checkboxes for termination info (I've seen more that do, but 10 years later and in Europe), then they might just have missed it completely.
NAG came a year later, again done by Edwards, who wisely reserved indecies for future definition. Apparently it never occured to Edwards to attribute some of these reserved glyphs to the different terminations that he instead incorporated as 'optional tag pairs'.
Again, the why he did so is most likely lost with the man. But keep in mind these protocols were designed to allow for a client independent way of simply parsing a chess game, and NAG in particular to annotate games very efficiently. The related termination data may not even be at hands when the stagist had to type in scoresheet data via keyboard, so much better to have the option, but not the duty to.

10380: <p>Suppose a chess game was decisive but didn't go to checkmate. Why does its notation not say whether the loser resigned or lost on time?</p>
<p>There are plenty of NAG symbols; even some ($136-$139) relating to time pressure. Why not for &quot;White/Black resigns&quot; or &quot;White/Black lost on time&quot;?</p>
<p>If we don't know because the only information known is what's on the scoresheets, then that doesn't answer the question; it merely redirects its focus: Considering that this fact is needed so that people know, and can say, how the game ended, why hasn't FIDE made it a law that players should record this on their scoresheets?</p>
<p>I know that <a href="https://chess.stackexchange.com/a/14571">players are not obliged to record this</a>. I'm asking <em>why</em> it has not been thought necessary to oblige players to do this.</p>
<p>I know that PGN has a <code>Termination</code> tag, whose value is a string which someone might use to explain how come the game ended. But a game's score can be stated in a context which is not PGN. Even in a PGN file, the tags pertaining to a game are not part of its score (what PGN calls its &quot;movetext&quot;). Even among PGN tags, <code>Termination</code> is optional.</p>
 32606: <p>An answer to your question needs to go back to the beginning of PGN, which was invented by Steven Edwards in conjunction with countless contributors. Let's quote the man:</p>
<blockquote>
<p>...it is important that future revisions to PGN must include a public discussion period. In fact, those of you who were reading the chess newsgroups back in the 1992-1994 time frame will recall the many polls and extensive discussion articles. I personally received uncounted hundreds, perhaps thousands of e-mails on the chess standards topics...</p>
</blockquote>
<p>This teamwork under Stevens lead happened on rec.games.chess (to be found <a href="https://groups.google.com/g/rec.games.chess.computer" rel="nofollow noreferrer">here</a>). Todays kids can think of a discord server.</p>
<p>It is unlikely someone is going through all of it, and sadly, Edwards has passed away.</p>
<p>Most likely, they couldn't see a need for this since you really only miss the distinction between flagging and resigning, and what's the point of knowing when there is no move time indication anyway.</p>
<p>Another hint could be given by the paper scoresheets they had at their hands; if these didn't feature checkboxes for termination info (I've seen more that do, but 10 years later and in Europe), then they might just have missed it completely.</p>
<p>NAG came a year later, again done by Edwards, who wisely reserved indecies for future definition. Apparently it never occured to Edwards to attribute some of these reserved glyphs to the different terminations that he instead incorporated as 'optional tag pairs'.</p>
<p>Again, the why he did so is most likely lost with the man. But keep in mind these protocols were designed to allow for a client independent way of simply parsing a chess game, and NAG in particular to annotate games very efficiently. The related termination data may not even be at hands when the stagist had to type in scoresheet data via keyboard, so much better to have the option, but not the duty to.</p>
