That's a great point. I think it's very much dependant on the audience as well as delivery. One would hope that people you work with are receptive to curiousity

That's a great point. I think it's very much dependant on the audience as well as delivery. One would hope that people you work with are receptive to curiousity, however it's not a given. In those cases I tend to give a little bit of background as to why I want to know why. It helps show the person that you trust them, but you're curious anyway. Eg. "I think I missed some of the prior meetings on this, why is this the best option?" It adds a little bit of humility that prevents it from sounding confrontational. Sometimes I'll ask something that gets to the bottom of why without asking it directly. Asking "Did we test the other options before choosing this one?" Can help someone to elaborate their why and making yourself an active participant rather than listener only.