I have worked in a number of software companies, and all of which have their own idiosyncrasies, which is perfectly understandable. The problem is, that some of these are (objectively) not good practices or counterproductive, or just plain odd and time-wasting.
When challenging some of these issues, an extremely common response is "this is how we always do it" or "that's how we do things here" as though that is justification in itself for the preservation of said practice. And despite offering decent counter-arguments, these phrases often seem to stop the conversation dead, and no further discussion takes place.
What would be a productive way to push for more productive reasoning for maintaining these practices and to not rock the boat, especially when fairly new to a company?
EDIT: It's not really so much about wanting people to adopt my ideas, but how to continue productive discussion when these phrases are dropped, as it happens so commonly and often acts as a full stop to discussion.