If you ask my why and then go on about how you dont want excuses, the convo is over.

A reason is an explanation although not all explanations are reasonable.

An excuse is an attempt to justify a reason/explanation.

Excuses are used when the expiation is not reasonable.

The mistake here is that the person explaining is interested in things like being correct or promoting efficiency while the adversary is only interested in hierarchy and dominating the explainer within their social context. That's the miscommunication happening.

I think this person asking you is really trying to tell you you did something the wrong way, but in a less direct manner, because directness is considered "rude" in some cultures.

More often than not it's more appropriate to say "I misunderstood, how should it have been done?" or "Sorry, I wasn't paying attention. I'll be more careful" which may or may not include an apology depending on whether you inconvenienced someone else.

A reason is a motivation to do a thing. An excuse is a reason to do the wrong thing (though not necessarily an inherently wrong thing - just anything that the other person thinks was wrong).

excuses lend themselves to lengthy explanations. reasons are more succinct and pertinent

I really dislike rhetorical questions.