This is a very misunderstood article. The money they "create", i.e loaned or paid out, has to be funded by a deposit or similar borrowing. Making sure they can fund all their commitments is what liquidity managers and treasury departments do, it's why regulators subject banks to annual ILAAPs (Internal Liquidity Adequacy Assessment Process), it's why banks have liquidity risk and modelling teams to manage any "gap" risk banks are running in this respect.
If banks could simply create money then they'd never go bust. The only exception is the Central Bank, which can create new money that is it uses to buy assets of the same value, supporting prices and improving liquidity in the financial system.
