I also like grinding - which I guess is not that much of an unpopular opinion in this thread :D
When I lose someone on my team I have to get someone else in shape, it's fun seeing them gradually get better at beating the mons they are grinding on. And only after a while can they become full members of the team. It makes a death more costly and thus more 'real' to me. If you can easily just rarecandy another mon in place of the fallen one, the death seems meaningless. It also makes the decision to grind a very low level mon unappealing, increasing diversity. When my levels are 40 for example and I have a lv 5 Magikarp in the box and a lv 35 Sharpedo - it makes much more sense to go with the Sharpedo, instead of another Gyarados.
When I lose someone on my team I have to get someone else in shape, it's fun seeing them gradually get better at beating the mons they are grinding on. And only after a while can they become full members of the team. It makes a death more costly and thus more 'real' to me. If you can easily just rarecandy another mon in place of the fallen one, the death seems meaningless. It also makes the decision to grind a very low level mon unappealing, increasing diversity. When my levels are 40 for example and I have a lv 5 Magikarp in the box and a lv 35 Sharpedo - it makes much more sense to go with the Sharpedo, instead of another Gyarados.