There are straightforward operational explanations for yesterday's profit downgrades from Customers and Credit Corp, both niche providers on the fringes of the banking sector.Their coincidence may be an indicator of wider trends; of frustrated growth plans, economic factors restraining profit growth, and management teams fast reassessing the earnings outlook in a climate of rising interest rates.Customers Limited, which now describes itself as the largest independent owner of automatic teller machines in Australia, cut its forecast for full year revenue to between $80 million and $85 million from a prior full year forecast of $93 million. Customers also said it would take a write down on its investment in Hong Kong-listed Fintronics.Lower transaction volumes on the company's ATM fleet in Australia are the main reason for the lower revenue forecast, an issue alluded to at the company's annual meeting in November.Explanations offered include the growth in the ATM fleets of a couple of banks (ANZ and National Australia Bank) including steady marketing by those banks to customers of the merit of using bank-branded ATMs; increases in the level of "foreign" ATM fees; and the temporary effects of smoking restrictions in pubs and clubs as well as tough times for many bush pubs (though the breaking of the drought may reverse this trend).Customers used its business update, published via the ASX yesterday morning, to disclose a couple of other details.One is that the banking industry has now agreed on 3 March 2009 as the final target date for the implementation of direct charging at ATMs.MasterCard has also increased its investment in Strategic Payments Services, the switch co-owned along with Customers and Bendigo and Adelaide Bank, with each now having a one third stake in the switching service.