Unfinished Chess game between Viswanathan Anand and Garry Kasparov I found many historic games unfinished.
Take this match as an example.
This is a match between Viswanathan Anand and Garry Kasparov in Ch World (match) (PCA) 1995. Anand lost this match as per the result. But I didn't find any confirmed checkmate in the last. Please somebody explain.
High level players usually resign when they have a lost position. There's no point in continuing the game for thirty more moves when defeat is inevitable. Checkmate is actually a rare occurence in elite games. You'll find the same thing in more modern games, too.
While players have the right to keep playing, it is considered bad etiquette to not resign when a player has no realistic chance of scoring.