Depends, depends, depends.
Grinding as a concept I don't like since it leaves far too much up to the developer, developers that usually do a pretty shit job at utilizing it.
Grinding was never meant to be something left solely up to the player, it was never meant to be something that was "part of the design but not designed itself", and that's the problem with it in a lot of games.
I remember back when I was playing Hyperdimension Neptunia's first remake and I was wondered, despite the extra areas using repeated designs of existing ones, despite the enemies being recolors as well, and ultimately, despite there being no reason to even clear the areas, why I went out of my way to clear these areas.
The answer was ultimately that I just liked doing the content in the game because it always knew how to make you feel rewarded for it. Even though the battle system isn't the most enticing in that game, I enjoyed it because it rarely felt like I was battling for no reason, and there was always a reason to challenge strong enemies or go out of my way to attack enemies that were there. That's an appropriately designed grind experience.
Conversely, look at Final Fantasy XIV's Forbidden Land of Eureka. Or the Diadem. For some reason the developers of this game can't get it through their thick heads that grinding up against high health enemies isn't actually fun in this game because it's a traditional rotation-based MMO. It feels boring to just rotation over and over and over again and the difference between this type of content and any other is either
A: Enemies have much lower health so doing damage just generally feels better
or
B: The area or enemies are designed in such a way to make the encounters interesting (this is why dungeons in the game are fun)
But if you just throw enemies in an area with big-ass health bars that do a lot of damage and give menial exp and rewards, it's just plain boring. Persona 1 also had this same problem, as well as a slew of turn-based RPGs throughout the third to sixth (arguably fifth) generations of gaming.
Just make a game that's fun to screw around with or rewards play and you'll be well off, you don't really have to do much to make grinding fun, but disregarding it altogether and just leaving it to the player makes for a tedious gameplay experience.