This practice of ringing your current provider to give them 'the chance' to be competitive is enabling the dysfunctional market. All its doing is getting the consumer closer to their point of inertia. 'Its not worth the hassle to send on the documents to the new crowd for a saving of €x'
They should be encouraged to offer the best price, first time. From the insurance company's point of view, in say 50% of renewals, the customer will call them back and say 'this is price that at which I will allow you to maximise your economic surplus'. How does that get you a competitive quote? At best it gets you into a position where you avoid the hassle of emailing your NCB to another company but you haven't, in fact, avoided the hassle at all, with all the phone calls back and forth!
When I switched energy provider, from Energia, they called to say 'Oh we have a better deal for switchers, its not on the website'. They didn't ring me to offer the great deal when my contract expired, they rang me after I initiated the switch. At least some of the mortgage suppliers tell you how much they will screw you after the fixed rate deal expires!