"Why?" is actually a word that we ask quite often if we are told to do something. Of course there is a right place and time for things. If my teacher tells me to do homework, I'm obviously not going to ask why. If my boss asks me to do something I am never going to ask why. If I was in the military and an officer who was above me told me to do something I wouldn't ask any questions. ESTJ's are great at following orders, almost as good as we are at giving them. I would almost never ask why to anyone who was above me. If I was the boss as well, I would never be okay with someone asking that, however I could tolerate it, except of course if I was in the military.
In a place where everyone is on the same level, why is my middle name. It is important for me to know why someone is doing something especially if to me it seems like a silly way to go about things. Someone once asked me to tell one of my friends something that was untrue just to be mean and I'm glad I asked why. In that case this person didnt have an answer and so I absolutely didnt do it. We like evidence and facts, so unless its a superior telling us what to do, we want to know these facts.
If you asked me why, I wouldn't have any problem answering. ESTJ's always have a logical reason for doing things, with a lot of evidence to back it up, so if you asked, I'd have no problem telling you my reasons. What does annoy me is when I ask my sister to help me carry something or do something around the house and she says why. My answer is always just "because that would be the nice thing to do". It bothers me that she doesnt get that.
ESTJ's place a lot on status levels. You are absolutely expected to obey what your superior says without asking questions. you are supposed to follow the rules and not ask about those either. If everyone stopped obeying their superiors nothing would ever get done. And like I said it infuriates me when people ask why to something that clearly means just doing something nice for someone. I just expect people to help each other and do things for each other, no questions asked, no pay back needed. People are expected to pull their weight. We really like things to be fair and if everyone is pulling their weight then its fair. So I'll get mad if someone asks why clearly because, like my sister, they just dont want to do something. But if I haven't explained why already, which is rare, I'm happy to answer.