KT's Lee Kang-chul's pitcher substitutions are goosebump-inducing

Honestly, what manager changes pitchers in the middle of an inning—whether it's the first batter or with runners on—when the score is 2-0 or 2-2, just to finish the last 5 outs? lol. Plus, there are more successes than failures; I feel like his approach is on a different level.
If a manager from another team did this, they would get heavily criticized and see many bad results.
KT used to rely heavily on their pitching staff, but now that their depth has improved, it seems they are also managing their fielders well, including effective use of pinch hitters and defensive replacements.