Some more persistent customers did manage to force BT to back down.
It didn't take into consideration all the special touches that made browsing at Bloomingdale's and Macy's stores so memorable, like the cranky shoe sales clerks capable of ignoring even the most persistent customers.
And the more persistent the customer, the more effort these companies expend on rebuffing them.
His two-year £7bn Project Spring capital expenditure top-up – designed to get Vodafone's 3G and 4G networks up to speed – may have landed in time to halt the persistent drip of customer defections.
In the confusion comes an attempt by the machines to gain control, which then leads to more problems and persistent issues for customers.
It is synchronized so a customer gets persistent sessions so a customer can end one session on a laptop and start another on a smartphone.
But increasingly, with persistent budget crunches, rising customer expectations, and nagging infrastructure issues, it's coming to the center stage.
Bank of America, seeking ways to resolve persistent image problems with customers, said on Thursday that it was making a major change to its lineup of advertising agencies.
When an organisation becomes mired in a scandal, struck by a crisis, or suffers persistent underperformance, its investors, customers, regulators, and employees can lose confidence in its capacity to deliver, and disengage.
Be persistent -- some potential customers may on-the-fence about using your merchandise, and this is a sure way to persuade them otherwise.
