I recently joined a very old company, with many lifers, I continuously run into this mentality. “I can’t explain it now, but I’m sure there was a good reason for it, so we’re gonna continue doing it this way”

The real issue is that most business just don't document anything to do with their processes. Chance are that there are a hand full of things that there are a good reason for doing and they do need to be done that way. Except the people that identified that original problem and came up with original solution have all left the company so now there is nobody around that has put in the effort (or been given the time to investigate) to figure out why things are done the way they are, and the last time one of the things that had been done forever was suddenly stopped it caused untold amount of chaos so now the directive is to just keep doing everything we've always done.

Of course it is typically wise to consider Chesterton's fence.

Per Chesterton's Fence, isn't this the right course of action for any individual who is unsure of why the practice was started?

https://www.lesswrong.com/w/chesterton-s-fence

I like that fence, but I consider the best course of action to be going and finding out why the thing is done the eay it is, even if it necessitates careful investigation.

I'd wholeheartedly agree with your assessment of the best course of action. To the points raised in the conversation above: there is definitely too little understanding of the pattern and too much blind adherence to the pattern as a widespread institutional practice across many institutions.

I always understood chestertons to be that you should leave the fence there while you are investigating why its there and whether its still needed. Not blind "dont do anything"

The extension to that is making it illegal to own/buy/use 'magic item Y', on the basis it enables fraud.

When they could just cut out the middle man and just make fraud itself illegal and not require the magic item at all.

ARM had a huge headache when the CEO of their Chinese subsidiary stole the company seal and refused to give it back. That meant they effectively couldn't do business at all.