The one most people know from the 1990s (Definitely on Windows 3.1, and probably Win 95) specifically was won only when all non-mine spaces were safely revealed. I know in my own case at least, I determined early on that flags were superfluous and ignored them in favour of better times.
But maybe at some point there was a game mode that let you finish by marking flags only, even when clear squares weren’t all revealed? It wouldn’t be the main game mode (or even present in the version I know), but I could see if that existed out there somewhere.
edit
I saw it confirmed by someone below there are indeed people playing newer versions of the game that have a “guess-free” mode.
The one most people know from the 1990s (Definitely on Windows 3.1, and probably Win 95) specifically was won only when all non-mine spaces were safely revealed. I know in my own case at least, I determined early on that flags were superfluous and ignored them in favour of better times.
But maybe at some point there was a game mode that let you finish by marking flags only, even when clear squares weren’t all revealed? It wouldn’t be the main game mode (or even present in the version I know), but I could see if that existed out there somewhere.
edit I saw it confirmed by someone below there are indeed people playing newer versions of the game that have a “guess-free” mode.