There seem to be a lot of trigger modifications & work available on handguns. (Maybe on long guns too, I don’t know.) How come? I understand the various handgrip and sighting options as post-production tailoring a gun to better fit one’s hand and sight. However all the trigger work discussion I’ve seen seems to be in terms of improving a ‘mediocre’ factory trigger design. The differences in the replacement trigger component pieces I’ve seen, although providing a big difference in trigger pull and reset, etc., I’m sure, are insignificant in terms of manufacturing process, considering the total production costs involved in a handgun. So, excepting competition shooting, if a lever, or something, that’s a just little bit longer or shorter, or whatever, provides a better trigger, why don’t they come like that from the factory? ??