part of the reason may just be that there's only one season a year, and you can't reasonably change the rules in the middle. i assume game devs are perfectly willing to push out balance adjustments more than once a year.
likewise there's limited opportunity to playtest -- MLB usually does this during spring training, for things like video reviews, the designated hitter, speed-of-play things, and so on.
likewise there's limited opportunity to playtest -- MLB usually does this during spring training, for things like video reviews, the designated hitter, speed-of-play things, and so on.