I have my reasons.
Get on the squirrel. There's no time to explain.
This is what you say when it's just too complicated. If it'd take you less time to kill the person you're trying to explain the situation to and hide the body than to get into it, it's time to whip out this phrase and leave it at that.
You have your reasons for doing things. Maybe you can't explain it. Maybe you can but you don't think you need to or should. We'll remind you that no amount of justification or rationalization in the world will fix stupid, so why bother? That's a lot of wasted effort for very little return. We say "very little" because maybe you enjoy watching humans get that look the dog gets after you fake throw the ball. But we digress. You know, sometimes people just need to be told that it's none of their business. This shirt can do that for you.
"I have my reasons." printed in white on a black, 100% cotton t-shirt.