You're in meeting trying to understand or solve some business problem - when someone throws out the dreaded "What if" or "How do we handle?" question. Sometimes it's a valid scenario. Sometimes it's an edge case, sometimes you suspect the person has been tripping and has taken it down some weird unrelated tangent.
It becomes a much larger problem when it drags the discussion into an infinite loop; When a decision can't be made because you're trying to handle so many different scenarios it's become a muddled mess.
At this stage - Park it.
Acknowledge the scenario, write it up on the whiteboard and agree to discuss at a later time. Most of the time it should end up being it's own scenario covered seperately..
I had a CTO once who was outstanding at this. He'd acknowledge what you brought up, write it up on the whiteboard and say "That's a great thought - Let's put that on the board, finish this off come back to that"
It took me several months to realize he never came back to any of it; Or had any intention to.
I guess that's less of a parking lot - More quicksand. He's probably a bad example.
...But what if he had come back to it…?