I worked for B of A for a while in their “Customer Retention” call center. First of all, why would a bank need a retention call center if they were treating their customers properly to begin with?
They would give high credit limits to high risk customers, let them run up their credit balances and then tell them they were going to raise their interest rates to some ridiculous number. Didn’t want to pay it? OK. Then you could “Opt Out”, which meant your account rate would be frozen but you had to pay it off as agreed. If you missed or was even a day late with a payment, or made even a $1 dollar purchase, they would automatically raise your interest rate to some God awful rate and retro charge it on the remaining balance on your acct. That put these people even further in debt. 
I did not stay there very long.