The company you pay for the retainer gets the retainer. For example a place I worked had a retainer with Verizon. Every month we paid Verizon ~$500/hr for X num

The company you pay for the retainer gets the retainer. For example a place I worked had a retainer with Verizon. Every month we paid Verizon ~$500/hr for X number of hours. If we didn't need those hours for incident response we could use them for penetration testing or consulting to improve our detection tools, etc. But when something bad happened, we had already pre-paid for their consultant to come visit and help us. The real benefit to this situation is you get to avoid haggling over price and waiting for a quote from the sales guy and running it past your legal department. All that enterprise sales nonsense is already done so when you pick up the phone it's all business with no negotiation.