[Negotiation] A cheaper option creates more operational risk. How do you explain why it may still be the wrong choice?

I would explain the decision in terms the business actually feels. If the cheaper option increases the chance of stockouts, customer impact, quality problems, or repeated expediting, then the savings need to be large enough to justify that exposure. Otherwise the lower quote is just moving cost somewhere less visible.

That kind of explanation usually lands better than saying procurement prefers the safer supplier. I want the stakeholder to...