The botched IT upgrade at TSB which left thousands unable to make payments could be down to a lack of proper testing, a report has revealed.
Computing giant IBM was called in to help the bank after its systems crashed in April, forcing TSB chief executive Paul Pester to admit the lender was "on its knees" as the crisis entered its second week.
In a report published by the Treasury committee, IBM said it would expect "world class design rigour [and] test discipline" before the bank carried out the migration.
However it instead found that "performance testing did not provide the required evidence of capacity".
It added: "IBM has not seen evidence of the application of a rigorous set of go-live...