You make them explain instead of explaining for them. Assuming what an answer means is a documented probing mistake because the key words are all ambiguous — “old” can mean fifteen years or forty, “expensive” can mean the total, the payment, or the surprise — and every assumption you make is a place the sale can quietly break later.
The short answer
The discipline is a reflex: whenever a loaded word lands — expensive, soon, later, fine, done right — the next move is a question that hands the definition back: what do you mean by that? what is that based on? The training repeats the rule across the objection material too, because it is the same skill at every stage: don't put words in their mouth, don't translate their language into yours, and don't assume every objection is fake — some are exactly what they sound like, and treating a real one as a smokescreen is its own failure.
How it runs
An assumption made in minute ten doesn't announce itself; it shows up in minute ninety as a presentation aimed at the wrong concern, priced against the wrong comparison, closed against an objection that was never the real one. That is why the discovery rule is stated without exceptions: the goal is clarity. A rep who would rather ask one more honest question than carry one comfortable assumption will lose a few seconds per appointment and save the whole sale several times a month.
Go deeper
Spar grades your probing against the documented system, round by round. Round 1 is free. Spar before you knock.